—n.
1 a person present at some event and able to give information about it (cf. EYEWITNESS).
2 a a person giving sworn testimony. b a person attesting another's signature to a document.
3 (foll. by to, of) a person or thing whose existence, condition, etc., attests or proves something (is a living witness to their generosity).
4 testimony, evidence, confirmation.
—v.
1 tr. be a witness of (an event etc.) (did you witness the accident?).
2 tr. be witness to the authenticity of (a document or signature).
3 tr. serve as evidence or an indication of.
4 intr. (foll. by against, for, to) give or serve as evidence.
Phrases and idioms:
bear witness to (or of)
1 attest the truth of.
2 state one's belief in. call to witness appeal to for confirmation etc. witness-box (US -stand) an enclosure in a lawcourt from which witnesses give evidence.
Etymology: OE witnes (as WIT(1), -NESS)
Useful english dictionary. 2012.