a shop selling ready-to-eat food products
"We stopped at the deli to buy some fresh sandwiches and cheese for our picnic."
A shop that sells cooked or prepared food ready for serving.
"We stopped at a deli to buy fresh pastrami sandwiches for lunch."
In plain English: A deli is a shop that sells ready-to-eat food and sliced meats for sandwiches.
"We bought sliced turkey from the deli for our lunch sandwich."
Usage: A deli refers specifically to a store selling pre-prepared foods like sandwiches and salads, distinct from a general grocery market where such items are merely available alongside raw ingredients. Use this term when describing the establishment itself rather than just referring to the counter or case of prepared meats found inside any supermarket.
The word "deli" is a shortened form of "delicatessen," which entered English in 1954 from the German plural Delikatessen. This term originally referred to fine foods or delicacies and traces its roots back through French and Latin to describe something delicate.