Aperitifs are appetizers, starters, and blue hour cocktails. An aperitif is a spiritous beverage taken before a meal as an appetizer. Originally Aperitifs were hardly appetizing - the word aperitif referred to a purgative.
They should whet the appetite, but never be served in quantities large enough to suppress it. These are the drinks with the highest esteem; cocktails are the most popular aperitif in the United States, while Southern Europe tends to prefer a complex alcohol, served straight or on the rocks.