Flat, n. 1. A level surface, without elevation, relief, or prominences; an extended plain; specifically, in the United States, a level tract along the along the banks of a river; as, the Mohawk Flats.
Envy is as the sunbeams that beat hotter upon a bank, or steep rising ground, than upon a flat. Bacon.
2. A level tract lying at little depth below the surface of water, or alternately covered and left bare by the tide; a shoal; a shallow; a strand.
Half my power, this night
Passing these flats, are taken by the tide. Shak.
3. Something broad and flat in form; as: (a) A flat-bottomed boat, without keel, and of small draught. (b) A straw hat, broad-brimmed and low-crowned. (c) (Railroad Mach.) A car without a roof, the body of which is a platform without sides; a platform car. (d) A platform on wheel, upon which emblematic designs, etc., are carried in processions.
4. The flat part, or side, of anything; as, the broad side of a blade, as distinguished from its edge.
5. (Arch.) A floor, loft, or story in a building; especially, a floor of a house, which forms a complete residence in itself.
6. (Mining) A horizontal vein or ore deposit auxiliary to a main vein; also, any horizontal portion of a vein not elsewhere horizontal. Raymond.
7. A dull fellow; a simpleton; a numskull.
Or if you can not make a speech,
Because you are a flat. Holmes.
8. (Mus.) A character before a note, indicating a tone which is a half step or semitone lower.
9. (Geom.) A homaloid space or extension.