flat

1a : lying at full length or spread out upon the ground : prostrate The soldiers were lying flat on the ground.

b : utterly ruined or destroyed buildings flat from the blast

c : resting with a surface against something Push the chairs flat against the wall.

2a : having a continuous horizontal surface the flat landscape of the prairie

b : being or characterized by a horizontal line or tracing without peaks or depressions a flat EEG

3 : having a relatively smooth or even surface a flat computer disk

4 : arranged or laid out so as to be level or even maps flat on the desk

5a : having the major surfaces essentially parallel and distinctly greater than the minor surfaces a flat piece of wood

b of a shoe heel : very low and broad flat shoes for work

6a : clearly unmistakable a flat denial

b(1) : not varying : fixed a flat rate

(2) : having no fraction either lacking or in excess : exact in a flat 10 seconds

(3) of a frequency response : not varying significantly throughout its range

7a : lacking in animation, zest, or vigor : dull He spoke in a flat, tired voice.

b : lacking flavor : tasteless The stew is too flat.

c : lacking effervescence or sparkle flat ginger ale

d : commercially inactive also : characterized by no significant rise or decline from one period to another sales were flat

e of a tire : lacking air : deflated

f chiefly British, of a battery : dead sense 3c, discharged

8a(1) of a tone : lowered a half step in pitch

(2) : lower than the proper pitch

b of the vowel a : pronounced as in bad or bat

9a : having a low trajectory (see trajectory sense 1) made a flat pass that was intercepted

b of a tennis stroke : made so as to give little or no spin to the ball

10 : not having an inflectional ending flat adverbs

11 of a sail : taut

12a : uniform in hue or shade figures standing out against a background of flat wash

b : having little or no illusion of depth

c of a photograph or negative : lacking contrast

d of lighting conditions : lacking shadows or contours

e : free from gloss : having a nonreflective finish a flat paint

f : two-dimensional sense 3 flat characters

13 : of, relating to, or used in competition on the flat a flat horse

14 of a universe : having a mass such that expansion halts only after infinite time and collapse never occurs

Definition of flat