What does "cove" mean?

Additional senses

1. 2.(Arch.) (a) A concave molding. (b) A member, whose section is a concave curve, used especially with regard to an inner roof or ceiling, as around a skylight.
2. 3.To arch over; to build in a hollow concave form; to make in the form of a cove. The mosques and other buildings of the Arabians are rounded into domes and coved roofs. H. Swinburne. Coved ceiling, a ceiling, the part of which next the wail is constructed in a cove. -- Coved vault, a vault composed of four coves meeting in a central point, and therefore the reverse of a groined vault.
3. 4.To brood, cover, over, or sit over, as birds their eggs. [Obs.] Not being able to cove or sit upon them [eggs], she [the female tortoise] bestoweth them in the gravel. Holland.
4. 5.A boy or man of any age or station. [Slang] There's a gentry cove here. Wit's Recreations (1654). Now, look to it, coves, that all the beef and drink Be not filched from us. Mrs. Browning.