Telltale

enthüllend

(revealing something)

verräterisch

(revealing something)

Anzeige

(something that serves to reveal)

Fadensonde

(nautical: yarn that indicates relative direction of airflow)

Hinweis

(something that serves to reveal)

Indikator

(something that serves to reveal)

Kontrolleinrichtung

(engineering: contrivance for indicating or recording something)

Petze

(one who divulges private information)

Petze

(tattletale; squealer)

Petzer

(one who divulges private information)

Petzerin

(one who divulges private information)