A delicatessen is a type of business. The term entered English via German, meaning "delicacies" but is ultimately of French origin. The term delicatessen has different meanings in different countries. In many countries a delicatessen may often be referred to informally as a deli.

In the United States, a delicatessen could be described as a synthesis of a fast-food restaurant and a grocery store. The delicatessen offers a wider and fresher menu than those found at chain fast food restaurants, rarely employing fry machines (except for chicken) and routinely preparing sandwiches to order.

A grocery store or supermarket may provide its own "deli" food, or even operate a delicatessen on-site. Like a market a delicatessen may also offer a selection of shelved food, often of the type that is not likely to be kept for more than a day. Produce, when present, is limited in quantity and often fresh. The Deli counter of a supermarket is where many people obtain their cold cuts.

Delicatessens vary greatly in size but are typically not as large as grocery stores. In areas with high rents for retail space, delicatessens are often quite small.

Delicatessens can come from a variety of cultural traditions. In the United States, most numerous are Jewish delicatessens, both kosher and "kosher style." As a result of this, Americans refer to those that specialise in Italian and German cuisine as "European Delicatessens."

In Europe, American Style Delis are provided largely by fast food outlets such as 'Subway'; this reflects the quality of produce available at these counters.