Histology Glossary - P

From Embryology
Embryology - 19 Mar 2024    Facebook link Pinterest link Twitter link  Expand to Translate  
Google Translate - select your language from the list shown below (this will open a new external page)

العربية | català | 中文 | 中國傳統的 | français | Deutsche | עִברִית | हिंदी | bahasa Indonesia | italiano | 日本語 | 한국어 | မြန်မာ | Pilipino | Polskie | português | ਪੰਜਾਬੀ ਦੇ | Română | русский | Español | Swahili | Svensk | ไทย | Türkçe | اردو | ייִדיש | Tiếng Việt    These external translations are automated and may not be accurate. (More? About Translations)

A Glossary of Histological and Micro-Anatomical Terms

 Histology Glossary: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z
Including historical origins and eponyms compiled by Dr Brian Freeman, Department of Anatomy, School of Medical Sciences, revised 2000.
ANAT2241 Support | Histology | Histology Stains | Historic Terminology | Embryology Glossary


Abbreviations: ( ) plural form in brackets, A. Arabic, abb. abbreviation, c. circa =about, F. French adj. adjective, G. Greek, Ge. German, cf. compare, L. Latin, dim. diminutive, NA. Nomina anatomica, q.v. which see, OF. Old French



Pacchioni, Antonio. 1665-1726 Rome & Tivoli anatomist; Pacchionian bodies = arachnoid granulations (1705), q.v.


pachymenix G. pachys = thick + menix = a membrane; the dura mater.


Pacini, Filippo. 1812-1883 Pisa & Florence anatomist; lamellated (onion-like) corpuscles of Vater-Pacini in skin (1840); tendon sheaths.


palate L. palatum = roof of mouth.


palisade L. palus = stake; like a fence of stakes.


palmate folds cf. plicae palmatae.


palpebral adj. L. palpebra = eyelid, from L. palpitare = to move quickly.


pampiniform adj. L. pampineus = full of vine tendrils + forma = shape; a tangled mass of veins in spermatic cord.


pancreas G. pan = all + kreas = edible flesh; a sweetbread (though less of a delicacy than the thymus); intestinal exocrine & endocrine gland.


pancreatic islets small islands or clusters of endocrine cells in pancreas; cf. Langerhans.


panniculus adiposus L. = a little piece of cloth, a rag + L. adeps = fat (adiposus is a L. corruption); the hypodermis (Berengarius, 1524).


Paneth, Josef. 1857-1890 Breslau & Vienna physiologist; P. cells (1887) = eosinophilic cells at base of intestinal crypts of Lieberkühn.


papilla (-ae) L. = a teat, a nipple; a nipple-like projection, e.g., on the tonge (Malpighi, c. 1670; cf. circumvallate, filiform, foliate, fungiform, vallate); duodenal papilla (containing duodenal ampulla); optic papilla; renal papilla (Berengarius, c. 1480-1550).


papillary adj. L. "; of the most superficial layer of the dermis, containing fine collagen fibres immediately under the epidermis; of cardiac muscle fibres that form eminences on the inner surface of the ventricles.


para- G. = beyond, beside, near.


paradidymis G. " + didymos = testicle; remains of mesonephros situated on the spermatic cord above the epididymis= organ of Giraldès, q.v.; also = organ of Waldeyer.


paraganglion (-ia) G. " + ganglion = a swelling; clumps of chromaffin tissue scattered alongside sympathetic nerves in thorax and abdomen; cf. Zuckerkandl.


parakeratin G. " + keras = horn; a type of keratin formed in superficial cells at sites of abrasion and rapid epithelial renewal, e.g., gingiva, tongue, tonsillar crypts, palate.


parametrium G. " + metra = womb, uterus; loose, fatty connective tissue in the broad ligament around uterus.


parathyroid G. " + thyreos = a shield (cf. thyroid gland); gland lying "alongside" the thyroid.


parenchyma G. " + enkeim = to pour in; the essential functional cells of an organ as opposed to its stroma, q.v. (NB. the accent is on the "e", not the "y").


paries (-ities) L. paries = a wall; cf. body wall around a coelom q.v.


parietal adj. L. parietalis = relating to walls; the outer region or wall as opposed to visceral.


paroöphoron G. para = beside + öon = egg + phoros = bearing; minute tubules of the mesosalpinx lying adjacent to the uterine tube, derived from caudal part of embryonic mesonephros.


parotid G. para = beside + otos = of the ear; a salivary gland.


parous L. pario = I bear (children).


pars L. = a part; a part of an organ, or structure, e.g., pars iridica retinae; pars nervosa; pars distalis, etc.


PAS periodic acid & Schiff's reagent; histochemical stain for carbohydrates involving production of aldehyde groups by initial treatment with periodic acid, then reaction of these groups with Schiff's reagent to produce a magenta colour.


pearl 1. a concretion formed around a grain of sand, etc.; 2. a small tough mass of material, e.g., a keratin pearl, an enamel pearl, a pearl of mucus in sputum.


pectinate adj. L. pecten = a comb; musculi pectinati = muscular bands passing forwards from crista terminalis in wall of right atrium (including the crista, resembles a comb).


pedicel L. pediculus = a little foot, dim. L. pes ; stem attached to growing process; pedicles of podocytes in renal glomerulus.


pedicle L. pediculus = a little foot (dim. of L. pes = a foot); stem or connecting stalk of a tumour; bony process connecting the lamina of a vertebra to its body; renal pedicle = renal "stalk".


pellucidum L. per = through + lucere = to shine; translucent; e.g., zona pellucida of ovarian follicle; septum p. of brain.


pelvis L. = a basin.


penicillar adj. L. penicillum = a paint-brush, from L. penna = a feather; branching into many short segments, as in the penicillar arterioles of the spleen


penis L. = a tail.


pepsinogen G. pepis = digestion + gennan = to produce; a precusor of pepsin = enzyme that aids digestion.


peri- G. = around, about.


pericardium G. " + kardia = heart; of two types: visceral (covering the heart) and parietal (lining the pericardial sac).


perichondrium G. " + chondros = granule, gristle, cartilage; connective tissue and cellular layer surrounding cartilage.


pericyte G. " + kytos = hollow vessel; mesenchymal cell adjacent to capillaries.


perikaryon G. " + karyon = nucleus; body of a nerve cell surrounding its nucleus; soma, q.v.


perilymph G. " + L. lympha = clear fluid; a bastard term (from G. & L.) for fluid in bony labyrinth surrounding the membranous labyrinth; cf. endolymph.


perimysium G. " + mys = muscle; connective tissue around a muscle fascicle.


perineurium G. " + neuron = sinew; a lamellated sheath of connective tissue and cells around a nerve fascicle.


periodontal ligament or membrane G. " + odons = tooth; fibro-elastic tissue (including Shapey's fibres) joining the tooth to its alveolar socket in the bone.


periodontium G. " ; all the tissue around the root of a tooth.


periosteum G. " + osteon = bone; fibrous membrane covering bone, attached to bony matrix by Sharpey's fibres.


peripheral nervous system nerves and nerve cells outside the central nervous system; abb. PNS.


peristalsis G. " + stalsis = a contraction, from stellein = to constrict; progressive contractile wave along body tubes (Culpeper, 1655); adj. peristaltic.


peritoneum G. peri = around + teinein = to stretch around; membrane stretched around the lining of the abdominal sac and ensheathing some viscera; adj. peritoneal.


Perls, Max, 1843-1881 German pathologist; Perls' test for hemosiderin using the Prussian blue reaction/stain.


Peyer, Johann Konrad. 1653-1712 Schaffhausen, professor of Logic, Rhetoric & Natural Science; P.'s patches = aggregated lymphatic nodules in terminal ileum (1673).


phagocytosis G. phagein = to eat + kytos = cell + osis = a condition of; process by which a cell engulfs foreign particles, dead material, etc.


phalangeal adj. G. phalanx = a band of soldiers (a Greek army division in battle order); phalangeal cells = sustentacular cells in organ of Corti whose processes extend upwards between the hair cells like fingers; Deiters, q.v.


pharynx G. = throat; adj. pharyngeal (? G. pharanx = a cleft, chasm).


pheomelanin G. phaios = dusky red + melas = black; pigment found in red hair.


phlegm G. phlegma = thick mucus; one of four humours of early physiology; thought to be a discharge from brain; cf. pituitary.


Phloxine red cytoplasmic dye.


photoreceptor G. phos = light + L. recipio = I receive; bastard term for light-sensitive cells in retina.


physic G. physikos = natural; the art of medicine.


pia mater L. pius = soft, faithful (L. pietas was one of the cardinal virtues) + mater = mother; delicate vascular membrane which adheres to surface of brain and spinal cord, faithfully following their contours.


picric acid a yellow dye.


pilomotor L. pilus = a hair + motor = mover; causing hair movement; cf. arrector pili.


pineal L. pinea = pine cone; cone-shaped gland of the brain; cf. conarium.


pinocytosis G. pinein = to drink + kytos = cell + osis = a condition of; process by which a cell takes in droplets of fluid.


pituitary L. pituita = phlegm, snot; gland at base of brain thought to be responsible for nasal secretion, via perforations in cribriform plate of ethmoid (Vesalius, c. 1560).


placenta L. = a flat cake, from G. plax - = flat- ; (Ge. Mutterkuchen = "mother-cake" = placenta).


plasma G. = a thing formed; liquid component of lymph, blood; NB. plasma membrane = cell membrane.


plasmodium G. " + -oeides = like; a continuum of protoplasm in which many nuclei are embedded, e.g., placental plasmodium = syncytiotrophoblast.


plasmolysis G. " + lysis = solution; shrinkage of a cell due to osmotic pressure.


platelet OF. plate = flat; small, non-nucleated discoids in circulating blood derived from fragmentation of megakaryocytes.


pleomorphic G. pleon = more + morphe = form; varying in shape and size.


pleura (-ae) G. = rib, side; serous membrane covering lungs and lining thorax; parietal and visceral pleurae.


plexus (-i) L. = a braid; a woven network of linear structures, especially nerves.


plica (-ae) a corruption from L. plicare = to fold; in13th century a scalp infection endemic in Poland was called plica polonica (Polish plait); any kind of fold.


plicae circulares L. = circular folds; actually transverse folds that are not circular in small intestine = valves of Kerckring, q.v.


plicae palmatae L. " + palmatae = like palm trees; flat mucosal folds like palm fronds in uterine cervical canal.


podocyte G. podos = foot + kytos = hollow vessel (cell); cell in renal glomerulus with many feet (foot processes) and pedicels.


-poiesis G. = making or producing; suffix as in haemopoiesis, leucopoiesis.


polar body the smaller daughter nucleus of a fertilised dividing ovum.


polkissen Ge. = pole cushion; extraglomerular mesangial cells at vascular pole.


polychromatophilic G. polys = many + chroma = colour + philein = to love.


polymorphonuclear (abb. polymorph) adj. G. " + morphe = form; having a nucleus with different shapes (multiple lobes), e.g., a neutrophilic leucocyte.


polyploid G. " + -oeides = form of; G. = manifold; having several sets of chromosomes; cf. diploid, haploid, aneuploid.


polysome aggregation of ribosomes.


pore L. porus = hole, aperture; nuclear pore = aperture in nuclear envelope.


porta hepatis L. porta = door + hepatis = of liver; fissure at hilum of liver; NB. portal vein was vein entering porta hepatis.


porta lienis L. porta = door + L. lienis = of the spleen; fissure at hilum of spleen.


portal adj. L. portare = to carry; of a vascular system carrying blood between infundibulum and adenohypophysis = hypothalamohypophyseal portal system. (NB. portal vein is named from L. porta = door).


postcapillary venules smallest vessels which drain capillary beds into collecting venules.


postsynaptic membrane region of membrane on a second cell opposite a synaptic terminal of the first cell; cf. synapse.


prepuce L. praeputium = prepuce or covering of glans penis (? from G. pro + posthe = penis; or ? L. puteo = I stink, from smell of smegma, q.v.; thus uncleanliness is figuratively termed praeputia ).


presynaptic membrane region of a nerve cell at the synapse of a terminal bouton; cf. synapse.


progesterone G. pro = before + L. gerere = to bear; hormone from corpus luteum preparing the uterus for pregnancy.


prophase G. pro = before + phasis = phase, from phainein = to appear, to show; first stage in mitosis of somatic cells.


prostate G. pro = before + G. istanai = to stand, or ? L. statum = stood; standing before; male gland at base of ("before") bladder; Aristotle uses prostatai chirsoedeis = varicose prostate = seminal vesicles; Herophilus (c. 300 BC) uses prostatai adenoeideis = glandular prostate; Galen (c. 180 AD) uses prostatai for whole complex of seminal vesicles and prostate, based on animal dissections.


protoplasm G. protos = first + plasma = a thing formed; living matter (Purkinje).


proximal L. proxime = nearest (to the head, to a source, etc.); opposite to distal, q.v.


psammoma G. psammos = sand + oma = tumor; laminated concretions found in the pineal gland (cf. brain sand, acervulus)


pseudopodium (-ia) G. pseudos = false, fraud + podos = foot; temporary extension of a cell.


pseudostratified G. pseudos = false, fraud; simple epithelium where not all apical borders of cells reach lumen, thereby appearing to be stratified.


pseudounipolar G. " ; of a sensory ganglion cell, bipolar in embryo, but in adult having one axon which bifurcates into a central and a peripheral branch, the peripheral branch behaving as a dendrite, q.v.; cf. bipolar.


PTAH phosphotungstic acid and haematoxylin stain.


pubes L. = signs of manhood; hair of genital region.


pulmonary L. pulmo = lung.


pulp L. pulpa = soft, fleshy; central part of a tooth; parts of spleen; central part of a finger.


pulvinar L. = a cushioned couch (used by the gods); the raised posterior part of the thalamus, q.v.


punctum lacrimale L. = a point + of tears; opening of lacrimal duct at inner canthus of the eye.


pupil L. pupa = a girl, damsel, a doll (as in puppet); L. pupillae = small doll-like images seen mirrored in the eye, led to term pupilla for the central aperture of the iris (Cicero).


Purkinje (Purkyne), Johannes Evangelista, Ritter von. 1787-1869 Breslau pathologist, Prague physiologist; famous microscopist; early use of microtome; recognized importance of fingerprints (1823); P. cells = largest cerebellar neurones with extensive dendrites (1837); P. cells = conducting heart cells (1845); P. phenomenon = casting shadows of retinal blood vessels.


pyknotic G. pyknos = thick, close, compact + osis = condition; a nucleus with very condensed chromatin; a shrunken nucleus.


pylorus G. pyle = a gate + ouros = a guard; a gate-keeper, a janitor; distal, sphincteric orifice of stomach (Galen, c. 180 AD).


pyramidal cell G. pyramis = pyramid; cell in the cerebral cortex with a pyramid-shaped soma.




Histology Glossary: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | ANAT2241 Support | Histology | Histology Stains | Embryology Glossary

Cite this page: Hill, M.A. (2024, March 19) Embryology Histology Glossary - P. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Histology_Glossary_-_P

What Links Here?
© Dr Mark Hill 2024, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G