perspiration

perspiration
/perr"speuh ray"sheuhn/, n.
1. a salty, watery fluid secreted by the sweat glands of the skin, esp. when very warm as a result of strenuous exertion; sweat.
2. the act or process of perspiring.
[1605-15, in sense "a breathing through"; 1620-30 for current senses; < NL perspiration- (s. of perspiratio) imperceptible sweating, lit., a breathing through. See PERSPIRE, -ATION]
Syn. 1. PERSPIRATION, SWEAT refer primarily to moisture exuded by animals and people from the pores of the skin. PERSPIRATION is often regarded as the more polite word, and is often used overfastidiously by those who consider SWEAT coarse; but SWEAT is a strong word and in some cases obviously more appropriate: a light perspiration; the sweat of his brow. SWEAT is always used when referring to animals or objects: Sweat drips from a horse's flanks. It may also be used metaphorically of objects: Sweat forms on apples after they are gathered.

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Fluid given off by the skin as vapour by simple evaporation or as sweat actively secreted from sweat glands to evaporate and cool the body.

When the body temperature rises, the sympathetic nervous system stimulates eccrine sweat glands to secrete water to the skin surface, where it cools the body by evaporation. Human eccrine sweat is essentially a dilute solution of sodium chloride with trace amounts of other plasma electrolytes. In extreme conditions, human beings may excrete several litres of such sweat in an hour.

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 in most mammals, water given off by the intact skin, either as vapour by simple evaporation from the epidermis (insensible perspiration) or as sweat, a form of cooling in which liquid actively secreted from sweat glands (q.v.) evaporates from the body surface. Sweat glands, although found in the majority of mammals, constitute the primary means of heat dissipation only in certain hoofed animals (orders Artiodactyla and Perissodactyla) and in primates, including humans. Their secretion is largely water (usually about 99 percent), with small amounts of dissolved salts and amino acids.

      When the body temperature rises, the sympathetic nervous system stimulates the eccrine sweat glands to secrete water to the skin surface, where it cools the body by evaporation. Thus, eccrine sweat is an important mechanism for temperature control. In extreme conditions, human beings may excrete several litres of such sweat in an hour.

      Human eccrine sweat is essentially a dilute sodium chloride solution with trace amounts of other plasma electrolytes. In some cases a reddish pigment may also be present. In a person unused to heavy sweating, the loss of sodium chloride during a period of heavy labour or high temperatures may be great (see sodium deficiency), but the efficiency of the gland increases with use, and in acclimatized persons the salt loss is decreased.

      The apocrine sweat glands, associated with the presence of hair in human beings (as on the scalp, the armpit, and the genital region), continuously secrete a concentrated fatty sweat into the gland tube. Emotional stress stimulates contraction of the gland, expelling its contents. Skin bacteria break down the fats into unsaturated fatty acids that possess a pungent odour.

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Universalium. 2010.

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  • perspiration — [ pɛrspirasjɔ̃ ] n. f. • 1539; lat. perspiratio ♦ Physiol. Ensemble des échanges respiratoires qui se font par la peau. La perspiration est importante chez certains animaux (batraciens). Perspiration insensible : élimination de vapeur d eau par l …   Encyclopédie Universelle

  • Perspiration — Per spi*ra tion, n. [Cf. F. perspiration.] 1. The act or process of perspiring. [1913 Webster] 2. That which is excreted through the skin; sweat. [1913 Webster] Note: A man of average weight throws off through the skin during 24 hours about 18… …   The Collaborative International Dictionary of English

  • perspiration — 1610s, from Fr. perspiration (1560s), noun of action from perspirer perspire, from L. perspirare blow or breathe constantly, from per through + spirare to breathe, blow (see SPIRIT (Cf. spirit)). Applied to excretion of invisible moistures… …   Etymology dictionary

  • Perspiration — steht für: Schwitzen, bei Tieren die Wasserabgabe über die Haut Hautatmung, bei Tieren der Austausch von Sauerstoff und Kohlendioxid über die Haut …   Deutsch Wikipedia

  • Perspiration — (lat.), soviel wie Hautatmung, s. Atmung, S. 55. Die gasförmigen Ausscheidungen der Haut (Kohlensäure und Wasserdampf) werden als Perspiratio insensibilis der Schweißabsonderung (Perspiratio sensibilis) gegenübergestellt …   Meyers Großes Konversations-Lexikon

  • Perspiration — Perspiratiōn (lat.), Hautausdünstung; perspiratōrish, die Ausdünstung befördernd; perspirieren, ausdünsten …   Kleines Konversations-Lexikon

  • perspiration — ► NOUN 1) sweat. 2) the process of perspiring …   English terms dictionary

  • perspiration — [pʉr΄spə rā′shən] n. [Fr] 1. the act of perspiring; sweating 2. salty moisture given off in perspiring; sweat …   English World dictionary

  • perspiration — noun … OF PERSPIRATION ▪ bead, drop ▪ Great beads of perspiration trickled down his forehead. VERB + PERSPIRATION ▪ wipe ▪ He wiped the perspiration from his brow …   Collocations dictionary

  • Perspiration — Sweat redirects here. For other uses, see Sweat (disambiguation). Perspire redirects here. For the song by Gigolo Aunts, see Tales from the Vinegar Side. Perspiration The facial sweat of a runner ICD 10 R …   Wikipedia

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