ENGLISH
REFERENCE

flat

adj. · n. · adv.
US //ˈfɫæt// UK //flˈæt// flat
  1. 1 level and smooth (adj.)
    A2 Elementary

    having a smooth surface without any parts that are higher than others.

    having a horizontal surface without significant elevations or depressions.

    Example

    The ground was perfectly flat, making it a great place to pitch our tent.

    Example

    The valley floor is remarkably flat, stretching for miles before the terrain begins to rise into the foothills.
  2. 2 deflated (adj.)
    A2 Elementary

    having no air inside, usually because of a hole.

    lacking sufficient air pressure, typically referring to a pneumatic tyre.

    Example

    I was late for work because my bike had a flat tyre.

    Example

    The driver pulled over immediately upon realising that the rear left tyre was completely flat.
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  1. 3 without bubbles (adj.)
    B1 Intermediate

    describing a drink that has lost its bubbles and no longer fizzes.

    lacking carbonation or effervescence due to the loss of dissolved carbon dioxide.

    Example

    I forgot to put the cap back on the soda, and now it tastes flat.

    Example

    The champagne had been left open overnight and had gone entirely flat by the time brunch was served.
  2. 4 dull or boring (adj.)
    B2 Upper Intermediate

    not interesting or lacking energy.

    lacking interest, excitement, or emotional variation.

    Example

    The actor's voice was very flat, so the play felt quite boring.

    Example

    Despite the high stakes, the candidate delivered her speech in a flat, uninspiring tone that failed to move the audience.
  3. 5 musical pitch (adj.)
    B2 Upper Intermediate Music

    lower in pitch than the correct note.

    below the intended or true pitch; specifically, lowered by a semitone.

    Example

    The piano sounds a bit flat, so we need to call a tuner.

    Example

    The choir director noted that the sopranos were slightly flat during the final chorus of the anthem.
    • lowered
  4. 6 an apartment (n.)
    A2 Elementary British English

    a set of rooms for living in that are part of a larger building.

    a residential suite occupying part of a building, typically on a single floor.

    Example

    They live in a small flat on the third floor of the building.

    Example

    Finding an affordable flat in the city centre has become increasingly difficult for young professionals.

    Usage

    In British English, 'flat' is the standard word, whereas 'apartment' is more common in American English.
  5. 7 shoes without heels (n.)
    B1 Intermediate

    women's shoes that do not have high heels.

    a type of shoe with a very low or non-existent heel, usually plural.

    Example

    She wore flats to the party because she knew she would be dancing all night.

    Example

    The dress code was formal, but she opted for elegant flats due to a recent ankle injury.
    • pumps
    • ballet shoes
  6. 8 exactly (adv.)
    B2 Upper Intermediate

    exactly or precisely, especially when talking about time.

    precisely or exactly; often used to emphasise the speed or brevity of an action.

    Example

    He ran the race in ten seconds flat.

    Example

    The emergency crew arrived in five minutes flat, preventing the fire from spreading to the adjacent units.
  7. 9 completely (adv.)
    B2 Upper Intermediate Informal

    completely or absolutely, often used with 'broke' or 'refuse'.

    completely or utterly; used as an intensifier for certain adjectives or verbs.

    Example

    I can't go out tonight because I am flat broke.

    Example

    The manager flat refused to consider the proposal, citing a lack of available funding for the quarter.
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”). Doublet of plat and pleyt. The noun is from Middle English flat (“level piece of ground, flat edge of a weapon”), from the adjective. The algebraic sense was coined by Serre in a 1956 paper, originally as French plat.

Etymology 2

From an alteration (due to Scots flatt (“a level part of a structure”)) of Scots flet, flett (“inner part of a house”), from Middle English flet (“dwelling”), from Old English flet, flett (“ground floor, dwelling”), from Proto-West Germanic flati, from Proto-Germanic flatją (“floor”), from Proto-Germanic flataz (“flat”), from Proto-Indo-European pleth₂- (“flat”). Akin to Old Frisian flet, flette (“dwelling, house”). More at flet, flat₁.

Etymology 3

From Middle English flatten, from Old French flatir (“to knock or strike down, dash”), from Frankish flattjan (“to move the palm of the hand”), from Proto-Germanic flatjaną (“to make flat, flatten”).

Word family
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