\De*po"nent\, n. [L. deponenes, -entis, laying down.
See {Depone}, v. t.]
1. (Law) One who deposes or testifies under oath; one who
   gives evidence; usually, one who testifies in writing.
2. (Gr. & Lat. Gram.) A deponent verb.
Syn: {Deponent}, {Affiant}.
Usage: These are legal terms describing a person who makes a
       written declaration under oath, with a view to
       establish certain facts. An affiant is one who makes
       an affidavit, or declaration under oath, in order to
       establish the truth of what he says. A deponenet is
       one who makes a deposition, or gives written testimony
       under oath, to be used in the trial of some case
       before a court of justice. See under {Deposition}.

\De*po"nent\, a. [L. deponens, -entis, laying down (its
proper passive meaning), p. pr. of deponere: cf. F.
d['e]ponent. See {Depone}.] (Gram.)
Having a passive form with an active meaning, as certain
latin and Greek verbs.