Wiktionary
n. A small glass used to hold or measure a small quantity of liquor.
WordNet
Wikipedia
A shot glass is a small glass designed to hold or measure spirits or liquor, which is either drunk straight from the glass ("a shot") or poured into a cocktail. A "shot" of liquor is not the same as a " shooter".
Shot glasses decorated with a wide variety of toasts, advertisements and humorous pictures are popular souvenirs and collectibles.
Usage examples of "shot glass".
And before Coral could so much as open her mouth, the whore had put a shot glass on the bar and filled it full of whiskey.
He used a chrome shot glass to measure the whiskey and poured it carefully over the crushed ice.
She loved the man who sat behind the enormous desk with his cigar and his shot glass and his ledgers.
He saw a shot glass in front of Porter along with a half-filled water glass and a third-filled bottle of bourbon.
He produced a hip flask about the size of a canteen and reached for a convenient shot glass.
I looked hard at her, then drained my shot glass and set it aside with exaggerated care.
Green eyes hard, he set his shot glass on the desk between them, the soft click sounding louder than it should.