Ar"cha*ism (#), n. [Gr. , fr. ancient, fr. beginning: cf. F. archaisme. See Arch, a.]
1.
An ancient, antiquated, or old-fashioned, word, expression, or idiom; a word or form of speech no longer in common use.
2.
Antiquity of style or use; obsoleteness.
A select vocabulary corresponding (in point of archaism and remoteness from ordinary use) to our Scriptural vocabulary.
De Quincey.
© Webster 1913.