Answer: informer

AnswerCrossword Clue
INFORMERDime dropper
INFORMERCanary
INFORMERMcLaglen's famous role.
INFORMERBetrayer of a sort.
INFORMERMcLaglen's 1935 Oscar film, with "The"
INFORMERTattletale
INFORMERStool pigeon
informerone who informs (to pass on information, also ENFORM)
informerperson who informs against another, esp. for money or other reward
informerperson who informs or communicates information or news; informant