Faccina Stordita

A yellow face with a crumpled mouth and a cockeyed expression, as if tired and emotional from inebriation or smitten with love. Depicted with raised or furrowed eyebrows and at least one eye half-open. WhatsApp's design features a tongue hanging out. 

Meaning widely varies, but commonly conveys intoxication or infatuation. Its dazed expression may also represent such feelings or states as bewilderment, irritation, disgust, exhaustion, wackiness, or complete satisfaction.