- (chemistry) The atomic weight of an element or radical divided by its valence; the molecular weight of a compound divided by its combining power in a specific reaction.
- 1888, Thomas Sterry Hunt, A New Basis for Chemistry, page 149:
- In the proportion d : p :: 1 : v, as applied to any liquid or solid species, p does not represent its real equivalent weight, but the weight of the normal species which, by its condensation, gives rise to the liquid or solid.
- 1922, Leicester F. Hamilton, Calculations of Analytical Chemistry, page 38:
- The equivalent weight of an element or compound is that weight equivalent in reactive power to one atomic weight of hydrogen.