доносчик meaning in English

ear [ears]▼(slang: police informant)
noun
[UK: ɪə(r)] [US: ˈɪr]

informer [informers]▼(person who tells authorities about improper or illegal activity)
noun
[UK: ɪn.ˈfɔː.mə(r)] [US: ˌɪn.ˈfɔːr.mər]

rat [rats]▼(informer or snitch)
noun
[UK: ræt] [US: ˈræt]

snitch▼(informer, usually one who betrays his group)
noun
[UK: snɪtʃ] [US: ˈsnɪtʃ]

telltale [telltales]▼(tattletale; squealer)
noun
[UK: ˈtel.teɪl] [US: ˈtel.ˌtel]

whistle-blower [whistle-blowers]▼(one who reports a problem or violation to the authorities)
noun
[UK: ˈwɪs.l̩ ˈbləʊə(r)] [US: ˈwɪs.l̩ ˈbloʊə(r)]