1. tv. to point someone out; to identify someone (as having done something, been somewhere, etc.). Pete fingered Marty as being the one who arrived first.
2. n. someone who identifies criminals for the police; a police informer. (Underworld.) Taylor has become a finger for the cops.
3. n. an amount of liquor poured into a glass equal to the width of a finger. Britney said she only drank one finger, but the glass was five inches in diameter!