witness

IPA: wˈɪtnʌs

(uncountable) Attestation of a fact or event; testimony.
(countable) One who sees or has personal knowledge of something.
(countable, law) Someone called to give evidence in a court.
(countable) One who is called upon to witness an event or action, such as a wedding or the signing of a document.
(countable) Something that serves as evidence; a sign or token.
Jehovah's Witness

(transitive) To furnish proof of, to show.
(transitive) To take as evidence.
(transitive) To see or gain knowledge of through experience.
(intransitive, construed with to or for) To present personal religious testimony; to preach at (someone) or on behalf of.
To see the execution of (a legal instrument), and subscribe it for the purpose of establishing its authenticity.

Examples of "witness" in Sentences

Roth notes that after arriving at the university in 1979, she asked to work on the word witness or witnessing.
There is not a fact in it without a note of the name and address of the witness who can prove it -- the _witness_ -- observe me. '
The witness was reimbursed this witness* by the Solicitor-Gene - from the Duchy of Cornwall office* ral» he said* that this Mr.T. wa» by Mr. Gray.
Now it would take the smallest portion of common sense to know that there is no witness, dead or living, who could testify to such a fact, save a _false witness_.
Well that's good clarification but the term witness line is an old and well established term that refers to the line which connects the "bubble" and is generally drawn coincident on-center to some object the witness line refers to.