soplón
/soˈplon/ · B2 · noun · m
fink
🐀 soplón = soplar (to blow, to whisper tip) + -ón, one who blows the whistle
Soplón comes from soplar, which means to blow and also slang for to tip off or leak. The suffix -ón marks a person who habitually does something. So a soplón is someone who habitually blows secrets to others, like an informer.