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flat 1

adj. flat·ter, flat·test
a. Having a smooth, even surface: a flat field. See Synonyms at level.
b. Having a relatively broad level surface in relation to thickness or depth: a flat box.
a. Being in horizontal position; lying down: flat on his back.
b. Being without slope or curvature: a flat line on a chart.
c. Having a low heel or no heel: flat shoes.
3. Free of qualification; absolute: a flat refusal.
4. Fixed; unvarying: a flat rate.
5. Lacking interest or excitement; dull: a flat scenario.
a. Lacking in flavor: a flat stew that needs salt.
b. Having lost effervescence or sparkle: flat beer.
a. Deflated. Used of a tire.
b. Electrically discharged. Used of a storage battery.
8. Of or relating to a horizontal line that displays no ups or downs and signifies the absence of physiological activity: A flat electroencephalogram indicates a loss of brain function.
9. Of or relating to a hierarchy with relatively few tiers or levels: a flat organization chart.
10. Commercially inactive; sluggish: flat sales for the month.
11. Unmodulated; monotonous: a flat voice.
12. Lacking variety in tint or shading; uniform: "The sky was bright but flat, the color of oyster shells" (Anne Tyler).
13. Not glossy; matte: flat paint.
14. Music
a. Being below the correct pitch.
b. Being one half step lower than the corresponding natural key: the key of B flat.
15. Designating the vowel a as pronounced in bad or cat.
16. Nautical Taut. Used of a sail.
17. Informal Having small breasts.
a. Level with the ground; horizontally.
b. On or up against a flat surface; at full length.
2. So as to be flat.
a. Directly; completely: went flat against the rules; flat broke.
b. Exactly; precisely: arrived in six minutes flat.
4. Music Below the intended pitch.
5. Business Without interest charge.
1. A flat surface or part.
2. often flats A stretch of level ground: salt flats.
3. A shallow frame or box for seeds or seedlings.
4. A movable section of stage scenery, usually consisting of a wooden frame and a decorated panel of wood or cloth.
5. A flatcar.
6. A deflated tire.
7. A shoe with a flat heel.
8. A large flat piece of mail.
9. A horse that competes in a flat race. Also called runner.
10. Music
a. A sign (♭) used to indicate that a note is to be lowered by a semitone.
b. A note that is lowered a semitone.
11. Football The area of the field to either side of an offensive formation.
v. flat·ted, flat·ting, flats
1. To make flat; flatten.
2. Music To lower (a note) a semitone.
v.intr. Music
To sing or play below the proper pitch.

[Middle English, from Old Norse flatr; see plat- in Indo-European roots.]

flat′ly adv.
flat′ness n.

flat 2

1. An apartment on one floor of a building.
2. Archaic A story in a house.

[Alteration of Scots flet, inner part of a house, from Middle English, from Old English, floor, dwelling; see plat- in Indo-European roots.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.



Flat is usually a noun or an adjective, but it is sometimes an adverb.

1. 'flat' used as a noun

In British English, a flat is a set of rooms for living in, usually on one floor of a large building.

...a ground floor flat.
2. 'flat' used as an adjective or adverb

Something that is flat is not sloping, curved, or pointed.

Every flat surface in our house is covered with junk.
Use a saucepan with a flat base.

If something lies or rests flat against a surface, all of it is touching the surface.

He was lying flat on his back.
She let the blade of her oar rest flat upon the water.

A flat refusal, denial, or rejection is definite and firm, and not likely to be changed.

He has issued a flat denial of these allegations.
3. 'flatly'

The adverb corresponding to this meaning of flat is flatly, not 'flat'.

She has flatly refused to go.
The Norwegians and Danes flatly rejected the evidence.

Flatly goes in front of refuse and deny, but you put it after say and state.

He flatly refused to accept it.
Many scientists flatly denied the possibility.
I could use some money, Sarah told him flatly.
Collins COBUILD English Usage © HarperCollins Publishers 1992, 2004, 2011, 2012
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adv.1.flatly - in an unqualified mannerflatly - in an unqualified manner; "he flatly denied the charges"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


adverb absolutely, completely, positively, categorically, unequivocally, unhesitatingly He flatly refused to discuss it.
Collins Thesaurus of the English Language – Complete and Unabridged 2nd Edition. 2002 © HarperCollins Publishers 1995, 2002


In a direct, positive manner:
Informal: flat out.
The American Heritage® Roget's Thesaurus. Copyright © 2013, 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
بِصَراحَه، بصورة تامَّ
ákveîiî; eindregiî
kesin olarakkesinlikle


[ˈflætlɪ] ADV
1. (= without emotion) [read, recite] → monótonamente; [say, reply] → de manera inexpresiva
2. (= categorically, completely) [refuse, deny] → terminantemente, rotundamente; [contradict] → de plano
we are flatly opposed to itnos oponemos terminantemente or rotundamente a ello
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005


[ˈflætli] adv
[refuse, deny] → catégoriquement
(= without expression) [say] → impassiblement
Collins English/French Electronic Resource. © HarperCollins Publishers 2005


(= completely) refuse, deny, rejectkategorisch, rundweg; contradictaufs Schärfste; to be flatly against or opposed to somethingetw rundweg ablehnen; (in principle) → kategorisch gegen etw sein; to be flatly opposed to doing somethingkategorisch dagegen sein, etw zu tun
(= unemotionally) say, stateausdruckslos, nüchtern
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007


[ˈflætlɪ] adv (refuse) → categoricamente, nettamente
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995


(flӕt) adjective
1. level; without rise or fall. a flat surface.
2. dull; without interest. She spent a very flat weekend.
3. (of something said, decided etc) definite; emphatic. a flat denial.
4. (of a tyre) not inflated, having lost most of its air. His car had a flat tyre.
5. (of drinks) no longer fizzy. flat lemonade; (also adverb) My beer has gone flat.
6. slightly lower than a musical note should be. That last note was flat; (also adverb) The choir went very flat.
stretched out. She was lying flat on her back.
1. (American aˈpartment) a set of rooms on one floor, with kitchen and bathroom, in a larger building or block. Do you live in a house or a flat?
2. (in musical notation) a sign (♭) which makes a note a semitone lower.
3. a level, even part. the flat of her hand.
4. (usually in plural) an area of flat land, especially beside the sea, a river etc. mud flats.
ˈflatly adverb
definitely; emphatically. She flatly denied it.
ˈflatten verb
(often with out) to make or become flat. The countryside flattened out as they came near the sea.
flat rate
a fixed amount, especially one that is the same in all cases. He charged a flat rate for the work.
flat out
as fast, energetically etc as possible. She worked flat out.
Kernerman English Multilingual Dictionary © 2006-2013 K Dictionaries Ltd.
References in classic literature ?
"But the best of it was," said one, telling of the misfortune of a fellow diplomat, "that the Chancellor told him flatly that his appointment to London was a promotion and that he was so to regard it.
It was a beautiful, bounteous, blue day; the spangled sea calm and cool, and flatly stretching away, all round, to the horizon, like gold-beater's skin hammered out to the extremest.
Hunt had suggested, in their present extremity, that it should be killed for food; to which the half-breed flatly refused his assent, and cudgeling the miserable animal forward, pushed on sullenly, with the air of a man doggedly determined to quarrel for his right.
Now she fell flatly back on her pillows, the very breath gone out of her.
Trent was flatly told that the labour they required was absolutely unprocurable.
I don't believe it," cried Felicity flatly. "Who told you?"
"I am sure we are very glad--and we wish you all possible happiness," said Anne, very flatly and inadequately, as she felt.
As Austin Lewis* says, speaking of that time, those to whom the command 'Feed my lambs' had been given, saw those lambs sold into slavery and worked to death without a protest.** The Church was dumb, then, and before I go on I want you either flatly to agree with me or flatly to disagree with me.
To him, as he flatly declared, Fleet Street, in the midst of the hurry of London life, was the most interesting place in the world.
I cannot say that I remember it all exactly as you have described it; my wife declares flatly there is not a word of truth in it as far as she is concerned, and Mrs.
I was amused at the appearance of four or five old women who, in a state of utter nudity, with their arms extended flatly down their sides, and holding themselves perfectly erect, were leaping stiffly into the air, like so many sticks bobbing to the surface, after being pressed perpendicularly into the water.
--The Situation flatly stated.--Energetic Replies of Kennedy and Joe.