Equivalent /(ē̇*kwĭv"ȧ*lent)/

E·quiv·a·lent

Equivalent

a.
  1. Equal in worth or value, force, power, effect, import, and the like; alike in significance and value; of the same import or meaning.
    For now to serve and to minister, servile and ministerial, are terms equivalent.
  2. Equal in measure but not admitting of superposition; -- applied to magnitudes; as, a square may be equivalent to a triangle. (Geom.)
  3. Contemporaneous in origin; as, the equivalent strata of different countries. (Geol.)

Equivalent

n.
  1. Something equivalent; that which is equal in value, worth, weight, or force; as, to offer an equivalent for damage done.
    He owned that, if the Test Act were repealed, the Protestants were entitled to some equivalent. . . . During some weeks the word equivalent, then lately imported from France, was in the mouths of all the coffeehouse orators.
  2. That comparative quantity by weight of an element which possesses the same chemical value as other elements, as determined by actual experiment and reference to the same standard. (Chem.)
  3. A combining unit, whether an atom, a radical, or a molecule; as, in acid salt two or more equivalents of acid unite with one or more equivalents of base. (Chem.)

Phrases & Compounds
Mechanical equivalent of heat
the number of units of work which the unit of heat can perform. It is an outdated concept that had an important part in the development and acceptance of the conservation of energy and the establishment of the science of thermodynamics in the 19th century.

Equivalent

v. t.
  1. To make the equivalent to; to equal; equivalence. [R.]