from
The Collaborative International Dictionary of English v.0.48
Informer \In*form"er\ ([i^]n*f[^o]rm"[~e]r), n. [From {Inform},
v.]
1. One who informs, animates, or inspires. [Obs.] --Thomson.
[1913 Webster]
Nature, informer of the poet's art. --Pope.
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2. One who informs, or imparts knowledge or news.
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3. (Law) One who informs a magistrate of violations of law;
one who informs against another for violation of some law
or penal statute.
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{Common informer} (Law), one who habitually gives information
of the violation of penal statutes, with a view to a
prosecution therefor. --Bouvier. --Wharton.
[1913 Webster]
from
Bouvier's Law Dictionary, Revised 6th Ed (1856)
COMMON INFORMER. One who, without being specially required by law, or by
virtue of his office, gives information of crimes, offences or misdemeanors,
which have been committed, in order to prosecute the offenders; a
prosecutor. Vide Informer; Prosecutor.