flat

1 adjective flatter, flattest

1 SURFACE smooth and level, without raised or hollow areas, and not sloping or curving: a flat-bottomed boat | a perfectly flat sandy beach | flat as a pancake (=very flat): The countryside near there is flat as a pancake.

2 flat rate/price/fee etc a flat rate, price, amount of money etc is fixed and does not change or have anything added to it: We charge a flat fee for car hire.

3 TYRE/BALL having no air or not enough air in it

4 DRINK having lost its bubble 1 (1) s of gas and so not tasting fresh: This Coke must have been opened ages ago - it's completely flat!

—opposite fizzy (1)

5 NOT INTERESTING (not before noun) a performance, book etc that is flat seems rather boring

6 BATTERY BrE a flat battery (1) has lost its electrical power : go flat (=become flat): Have you checked that the batteries haven't gone flat?

7 BUSINESS/TRADE not busy: The building industry's been completely flat for several years.

8 E flat/B flat/A flat etc a musical note that is one semitone lower than the note E, B, A etc

9 MUSICAL SOUND if a musical note is flat, it is played or sung at a slightly lower pitch (pitch2 (3)) than it should be: The guitar was flat through the whole song.

10 VOICE not showing much emotion, or not changing much in sound as you speak: “He's dead,” she said in a flat voice.

11 flat refusal/denial etc a refusal etc that is definite and which someone will definitely not change: Our requests were met with a flat refusal.

12 and that's flat! spoken used to say that you will definitely not change what you have just said: I won't go, and that's flat!

13 be flat on your back

a) to be lying down so that all of your back is touching the floor: Arthur was flat on his back under the car.

b) to be very ill so that you have to stay in bed for a period of time

14 SHOES flat shoes have very low heels

15 NOT DEEP not very deep, thick, or high, especially in comparison to its width or length: a round, flat apple tart

16 LIGHT having little variety of light and dark: Flat lighting is typical of Avedon's portraits.

— flatness noun (U) —see also: fall/go into a flat spin spin 2 (4) 2 noun (C)

1 PLACE TO LIVE BrE a place for people to live that consists of a set of rooms that are part of a larger building; apartment AmE : They have a flat in Crouch End. | a ground-floor flat | a block of flats (=a large building with many flats in it)

2 TYRE especially AmE a tyre that does not have enough air inside; puncture BrE

3 MUSIC

a) a musical note that is one semitone lower than a particular note

b) the sign (b) in written music that shows that a note is one semitone lower than a particular note

—compare sharp 3, natural 2 (2)

4 LAND flats (plural) an area of land that is at a low level, especially near water: mud flats

5 the flat of sb's hand/a knife/a sword etc the flat part or flat side of something

6 on the flat BrE on ground that is level and does not slope: It's much easier walking on the flat.

3 adverb

1 FLAT POSITION in a position in which the surface of something is against another surface without curving or sloping : lie flat: He lay flat on the floor to look for it under the bed.

2 three minutes/10 seconds etc flat informal used to emphasize that something happens or is done very quickly: I was dressed in five minutes flat.

3 fall flat informal

a) if a joke or story falls flat, people are not amused by it: Oh Dear! My joke about fat people fell completely flat, didn't it?

b) if something you have planned falls flat it is unsuccessful

4 MUSIC if you sing or play music flat, you sing or play slightly lower than the correct note so that the sound is unpleasant

—compare sharp 2 (4)

5 fall flat on your face

a) to fall so that you are lying on your front on the ground

b) informal to not have the result you wanted or expected, especially when this is embarrassing: It is a wonderful theory, but falls flat on its face when put into practice.

6 flat out

a) informal as fast as possible: They were working flat out to get the job done on time.

b) AmE spoken in a direct way : ask/tell sb flat out: She asked him flat out whether he'd been seeing another woman.

7 tell sb flat BrE spoken to tell someone something directly and definitely: I told him flat that I didn't want to see him again.

8 go flat against BrE spoken to directly disobey someone or ignore them: I don't know why you bother to ask - you'll go flat against my advice anyway!

—see also: flat broke broke 2 (1)