INFORMANT
informant, source
(noun) a person who supplies information
witness, witnesser, informant
(noun) someone who sees an event and reports what happened
Source: WordNet® 3.1
Etymology
Noun
informant (plural informants)
One who relays confidential information to someone, especially to the police; an informer.
(linguistics) A native speaker who acts as a linguistic reference for a language being studied. The informant demonstrates native pronunciation, provides grammaticality judgments regarding linguistic well-formedness, and may also explain cultural references and other important contextual information.
Synonyms
• See Thesaurus:informant
Source: Wiktionary
In*form"ant, n. Etym: [L. informans, -antis, p.pr. of informare. See
Inform, v. t.]
1. One who, or that which, informs, animates, or vivifies. [Obs.]
Glanvill.
2. One who imparts information or instruction.
3. One who offers an accusation; an informer. See Informer. [Obs. or
R.]
It was the last evidence of the kind; the informant was hanged.
Burke.
Source: Webster’s Unabridged Dictionary 1913 Edition