A door that is divided horizontally into two parts such that the upper part may be opened independently of the lower.

An opening in a door where a dog can enter and leave a house without requiring a human to open the door.

A coarse mat at the entrance to a house, upon which one wipes one's shoes. / (figuratively, derogatory) Someone who is overly submissive to others' wishes.

An opening in a door for pets to come in and out of the house without requiring a human to open the door.

A door that slides into the wall.

Used other than figuratively or idiomatically: see barn, doors.

(simile) Entirely, unquestionably or certainly dead.

In an adjacent building, room or place.

(usually postpositive) That is in an adjacent place; that is located next door.

(dialectal) Next door to.