witness

v. look on, see, observe; testify, vouch for, corroborate; be an eye-witness; note, notice

n. testifier; onlooker, bystander; eye-witness; testimony

A witness is someone who has firsthand knowledge about a crime or dramatic event through their senses (e.g. seeing, hearing, smelling, touching) and can help certify important considerations to the crime or event. A witness who has seen the event firsthand is known as an eye-witness. Witnesses are often called before a court of law to testify in trials.
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Noun
1. someone who sees an event and reports what happened
(synonym) witnesser, informant
(hypernym) perceiver, observer, beholder
(hyponym) attester, attestant
2. a close observer; someone who looks at something (such as an exhibition of some kind); "the spectators applauded the performance"; "television viewers"; "sky watchers discovered a new star"
(synonym) spectator, viewer, watcher, looker
(hypernym) perceiver, observer, beholder
(hyponym) browser
(derivation) find, see
3. testimony by word or deed to your religious faith
(hypernym) testimony
(hyponym) shahadah
4. (law) a person who attests to the genuineness of a document or signature by adding their own signature
(synonym) attestant, attestor, attestator
(hypernym) signer, signatory
(classification) law, jurisprudence
5. (law) a person who testifies under oath in a court of law
(hypernym) person, individual, someone, somebody, mortal, human, soul
(hyponym) adverse witness, hostile witness
(classification) law, jurisprudence
Verb
1. be a witness to
(hypernym) watch
2. perceive or be contemporaneous with; "We found Republicans winning the offices"; "You'll see a lot of cheating in this school"; "I want to see results"; "The 1960 saw the rebellion of the younger generation against established traditions"; "I want to see results"
(synonym) find, see
(hypernym) experience, undergo, see, go through
(hyponym) catch
(verb-group) find
(derivation) spectator, viewer, watcher, looker

(v. t.)
To see the execution of, as an instrument, and subscribe it for the purpose of establishing its authenticity; as, to witness a bond or a deed.
  

(v. t.)
To see or know by personal presence; to have direct cognizance of.
  

(v. t.)
To give testimony to; to testify to; to attest.
  

(v. i.)
To bear testimony; to give evidence; to testify.
  

(v. i.)
That which furnishes evidence or proof.
  

(v. i.)
One who testifies in a cause, or gives evidence before a judicial tribunal; as, the witness in court agreed in all essential facts.
  

(v. i.)
One who sees the execution of an instrument, and subscribes it for the purpose of confirming its authenticity by his testimony; one who witnesses a will, a deed, a marriage, or the like.
  

(v. i.)
One who is cognizant; a person who beholds, or otherwise has personal knowledge of, anything; as, an eyewitness; an earwitness.
  

(v. i.)
Attestation of a fact or an event; testimony.
  

Person who witnesses a crime and gives evidence in judicial proceedings. The EU supports witnesses being able to give evidence in another Member State via video-conference technology. (see judicial-criminal)