Hardness
Hardness Hard"ness, n. [AS. heardness.] 1. The quality or state of being hard, literally or figuratively. [1913 Webster]

The habit of authority also had given his manners some peremptory hardness. --Sir W. Scott. [1913 Webster]

2. (Min.) The cohesion of the particles on the surface of a body, determined by its capacity to scratch another, or be itself scratched; -- measured among minerals on a scale of which diamond and talc form the extremes. [1913 Webster]

3. (Chem.) The peculiar quality exhibited by water which has mineral salts dissolved in it. Such water forms an insoluble compound with soap, and is hence unfit for washing purposes. [1913 Webster]

Note: This quality is caused by the presence of calcium carbonate, causing temporary hardness which can be removed by boiling, or by calcium sulphate, causing permanent hardness which can not be so removed, but may be improved by the addition of sodium carbonate. [1913 Webster]


The Collaborative International Dictionary of English. 2000.

Synonyms:

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  • Hardness — Hardness. См. Твердость. (Источник: «Металлы и сплавы. Справочник.» Под редакцией Ю.П. Солнцева; НПО Профессионал , НПО Мир и семья ; Санкт Петербург, 2003 г.) …   Словарь металлургических терминов

  • hardness — index brutality, congealment Burton s Legal Thesaurus. William C. Burton. 2006 …   Law dictionary

  • hardness — (n.) O.E. heardnysse; see HARD (Cf. hard) + NESS (Cf. ness). Meaning difficulty of action or accomplishment is late 14c …   Etymology dictionary

  • hardness — [härd′nis] n. 1. the state or quality of being hard (in various senses) 2. the relative capacity of a substance for scratching another or for being scratched or indented by another …   English World dictionary

  • Hardness — This article is about mechanical properties of materials. For other uses, see Hard. Hardness is the measure of how resistant solid matter is to various kinds of permanent shape change when a force is applied. Macroscopic hardness is generally… …   Wikipedia

  • hardness — /hahrd nis/, n. 1. the state or quality of being hard: the hardness of ice. 2. a relative degree or extent of this quality: wood of a desirable hardness. 3. that quality in water that is imparted by the presence of dissolved salts, esp. calcium… …   Universalium

  • Hardness — (Roget s Thesaurus) < N PARAG:Hardness >N GRP: N 1 Sgm: N 1 hardness hardness &c. >Adj. Sgm: N 1 rigidity rigidity Sgm: N 1 renitence renitence renitency Sgm: N 1 inflexibility inflexibility temper callosity …   English dictionary for students

  • hardness —    a measure of the hardness of a metal or mineral. Hardness is a property easy to appreciate but difficult to quantify and measure.    The Mohs hardness scale is used in geology to give a rough estimate of hardness by testing which minerals are… …   Dictionary of units of measurement

  • hardness — The toughness of the surface of a metal. See brinell hardness indentation hardness rockwell hardness shore hardness …   Dictionary of automotive terms

  • hardness — 1. The degree of firmness of a solid, as determined by its resistance to deformation, scratching, or abrasion. SEE ALSO: h. scale, number. 2. The relative penetrating power of a beam of x rays, used both within the diagnostic range of …   Medical dictionary

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