Pigment

Pigment
: A substance that gives color to tissue. Pigments are responsible for the color of skin, eyes, and hair.
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1. Any coloring matter, as that of the red blood cells, hair, iris, etc., or the stains used in histologic or bacteriologic work, or that in paints. 2. A medicinal preparation for external use, applied to the skin like paint, or coloring agents used in paints. [L. pigmentum, paint]
- bile pigments coloring matter in the bile derived from porphyrins by rupture of a methane bridge; e.g., bilirubin, biliverdin.
- chymotropic p. a p. dissolved in the vacuole of a plant cell. [G. chymos, juice, + trope, turning, inclination, + -ic]
- formalin p. a p. formed when acid aqueous solutions of formaldehyde act on blood-rich tissues; characterized by rotation of the plane of polarized light, withstanding extraction in aqueous and lipid solvents, being bleached in acids and hydrogen peroxide; not formed when tissue is fixed with formaldehyde buffered to pH levels above 6.
- hematogenous p. a p. derived from the hemoglobin of the red blood cells.
- hepatogenous p. bile p. derived from the destruction of hemoglobin in the liver.
- malarial p. a dark brown, granular p. that rotates the plane of polarized light and has other properties similar to formalin p.; occurs in parasites, such as Plasmodium malariae, around brain capillaries, and in fixed macrophages of spleen, liver, bone marrow, and lymph node s; composed of excess protein, an iron porphyrin, and hematin left over from the metabolism of hemoglobin by the malarial parasite within the red blood cell. See malarial p. stain.
- melanotic p. SYN: melanin.
- natural p. a naturally occurring colored compound; absorbs light in the visible range of the electromagnetic spectrum. Cf.:structural color. SYN: biochrome.
- respiratory pigments the oxygen-carrying (colored) substances in blood and tissues (hemoglobin, myoglobin, hemocyanin, etc.).
- visual pigments the photopigments in the retinal cones and rods that absorb light and initiate the visual process.
- wear-and-tear p. lipofuscin that accumulates in aging or atrophic cells as a residue of lysosomal digestion.

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pig·ment 'pig-mənt n a coloring matter in animals and plants esp. in a cell or tissue also any of various related colorless substances

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n.
a substance giving colour. Physiologically important pigments include the blood pigments (especially haemoglobin), bile pigments, and retinal pigment (see rhodopsin). The pigment melanin occurs in the skin and in the iris of the eye. Important plant pigments include chlorophyll and the carotenoid.

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pig·ment (pigґmənt) [L. pigmentum paint] 1. any normal or abnormal coloring matter of the body. 2. a paintlike medicinal preparation to be applied to the skin.

Medical dictionary. 2011.

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  • pigment — [ pigmɑ̃ ] n. m. • 1813; « épice » 1130; lat. pigmentum;cf. piment 1 ♦ Biochim. Matière colorée, de structure variée, présente dans divers tissus et organes végétaux ou animaux auxquels elle donne une coloration particulière. Pigments végétaux. ⇒ …   Encyclopédie Universelle

  • pigment — PIGMÉNT, pigmenţi, s.m. 1. Substanţă colorată naturală produsă de celulele plantelor şi animalelor şi care colorează în mod specific ţesuturile sau lichidele organice ale acestora. 2. Particulă solidă, colorată, insolubilă în mediul în care este… …   Dicționar Român

  • Pigment — Sn (Farbstoff) erw. fach. (18. Jh.) Entlehnung. Entlehnt aus l. pīgmentum Färbestoff, Farbe , zu l. pingere (pictum) malen, bestreichen .    Ebenso nndl. pigment, ne. pigment, nfrz. pigment, nschw. pigment, nnorw. pigment; Pinte, pittoresk. ✎ DF… …   Etymologisches Wörterbuch der deutschen sprache

  • Pigment — Pig ment, n. [L. pigmentum, fr. the root of pingere to paint: cf. F. pigment. See {Paint}, and cf. {Pimento}, {Orpiment}.] 1. Any material from which a dye, a paint, or the like, may be prepared; particularly, the refined and purified coloring… …   The Collaborative International Dictionary of English

  • pigment — pìgment (pigmȅnt) m <G mn nātā> DEFINICIJA 1. fiziol. tvar što je u tkivima sintetiziraju živa bića i koja tkivima daje boju 2. kem. mineralna supstanca (obično u obliku praha) koja služi kao sredstvo za bojenje ETIMOLOGIJA njem. Pigment ←… …   Hrvatski jezični portal

  • pigment — (n.) late 14c., from L. pigmentum coloring matter, pigment, paint, from root of pingere to color, paint (see PAINT (Cf. paint)). Variants of this word may have been known in Old English (e.g. 12c. pyhmentum) …   Etymology dictionary

  • pigment — ► NOUN 1) the natural colouring matter of animal or plant tissue. 2) a substance used for colouring or painting. ► VERB ▪ colour with or as if with pigment. DERIVATIVES pigmentary adjective pigmentation noun. ORIGIN …   English terms dictionary

  • pigment — vi. pigmentized, pigmentizing [pig′mənt] n. [ME < L pigmentum < base of pingere, to PAINT] 1. coloring matter, usually in the form of an insoluble powder, mixed with oil, water, etc. to make paints 2. any coloring matter in the cells and… …   English World dictionary

  • Pigment — Pigment, so v.w. Farbestoff (s.d.). Schwarzes P., 1) der Augen, so v.w. Melanin, vgl. Auge 1) A) e); 2) verschiedener Gewebe des Körpers, so v.w. Melanose. Daher Pigmentkrebs, s. u. Krebs a) …   Pierer's Universal-Lexikon

  • Pigmént — (lat.), soviel wie Farbstoff (s. Farbstoffe), besonders die im menschlichen Körper auftretenden Farbstoffe. Die Färbung der Regenbogenhaut und der Aderhaut des Auges, der Haut der Neger, der Sommersprossen und gewisser Hautflecke sind abhängig… …   Meyers Großes Konversations-Lexikon

  • Pigmént — (lat.), Farbstoff (s.d.), besonders der des tierischen und pflanzlichen Körpers …   Kleines Konversations-Lexikon

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