Definition flat
Etymology 1
From Middle English flat, a borrowing from Old Norse flatr (compare Norwegian and Swedish flat, Danish flad), from Proto-Germanic *flataz, from Proto-Indo-European *pleth₂- (“flat”); akin to Saterland Frisian flot (“smooth”), German Flöz (“a geological layer”), Ancient Greek πλατύς (platús), Latvian plats, Sanskrit प्रथस् (prathas, “extension”).
Adjective
flat (comparative flatter, superlative flattest)
- Having no variations in height.
- (music, voice) Without variations in pitch.
- (slang) Describing certain features, usually the breasts and/or buttocks, that are extremely small or not visible at all.
- (music, note) Lowered by one semitone.
- (music) Of a note or voice, lower in pitch than it should be.
- (of a tire or other inflated object) Deflated, especially because of a puncture.
- Uninteresting.
- Of a carbonated drink, with all or most of its carbon dioxide having come out of solution so that the drink no longer fizzes or contains any bubbles.
- (wine) Lacking acidity without being sweet.
- (of a battery) Unable to emit power; dead.
- (juggling, of a throw) Without spin; spinless.
- (figuratively) Lacking liveliness or action; depressed; dull and boring.
- Absolute; downright; peremptory.
- (phonetics, dated, of a consonant) sonant; vocal, as distinguished from a sharp (non-sonant) consonant
- (grammar) Not having an inflectional ending or sign, such as a noun used as an adjective, or an adjective as an adverb, without the addition of a formative suffix; or an infinitive without the sign "to".
- (golf, of a golf club) Having a head at a very obtuse angle to the shaft.
- (horticulture, of certain fruits) Flattening at the ends.
- (authorship, figuratively, esp. of a character) Lacking in depth, substance, or believability; underdeveloped; one-dimensional.
Adverb
flat (comparative more flat, superlative most flat)
- So as to be flat.
- Bluntly.
- (with units of time, distance, etc) Not exceeding.
- Completely.
- Directly; flatly.
- (finance, slang) Without allowance for accrued interest.
Noun
From 1795, alteration of Scots flet (“inner part of a house”), from Middle English flet (“dwelling”), from Old English flet, flett (“ground floor, dwelling”), from Proto-Germanic *flatją (“floor”), from Proto-Germanic *flataz (“flat”), from Proto-Indo-European *plat- (“flat”). Akin to Old Frisian flet, flette (“dwelling, house”). More at flet, flat1.
Noun
flat (plural flats)
- (chiefly Britain, New England, New Zealand and Australia, archaic elsewhere) An apartment, usually on one level and usually consisting of more than one room.
Etymology 3
From Middle English flatten, from Old French flatir (“to knock or strike down, dash”).
Verb
flat (third-person singular simple present flats, present participle flatting, simple past and past participle flatted)
- (transitive, obsolete) To beat or strike; pound
- (transitive) To dash or throw
- (intransitive) To dash, rush