Definition

1. Adjective:

   • Lying horizontally; level; without slope or tilt: Describing a surface that is even and smooth, with no part higher or lower than another.
   • Lacking air or effervescence; stale: Describing a drink, especially a carbonated one, that has lost its bubbles and become tasteless.
   • Unchanging in tone, pitch, or level: Describing a sound, voice, or situation that is monotonous, lacks variation, or shows no activity or growth.
   • Absolute; unqualified; without reservation: Used to emphasize that something is complete and direct.
   • Lowered in pitch by a semitone: In music, describing a note that is one half step lower than the natural note.

2. Noun:

   • A set of rooms for living in, typically on one floor of a building: A self-contained housing unit that is part of a larger building.
   • A level area of land; a plain: A tract of land that is smooth and even.
   • A deflated pneumatic tire: A tire that has lost its air pressure.
   • A musical symbol (♭) indicating a note is to be lowered by a semitone: The sign used in musical notation.

3. Adverb:

   • Completely; absolutely; in a direct manner: Used to emphasize that an action is total or a statement is frank.
   • Below the correct musical pitch: Singing or playing a note at a lower pitch than intended.

Usage and Examples

• Adjective:

  • The land here is very flat and suitable for farming. (Describing level terrain)
  • This soda is flat; it has no fizz left. (Describing a drink without bubbles)
  • She spoke in a flat, emotionless voice. (Describing a monotonous tone)
  • He gave a flat refusal to their proposal. (Describing an absolute denial)
  • The note B flat is common in this key. (Describing a lowered musical note)

• Noun:

  • They rented a small flat in the city center. (Referring to an apartment)
  • The car had a flat on the highway, so we had to stop. (Referring to a deflated tire)
  • The composer used an E flat in the melody. (Referring to the musical symbol or note)

• Adverb:

  • She told him flat that she was not interested. (Meaning directly or absolutely)
  • The singer went flat on the high note. (Meaning below the correct pitch)

Advanced Usage

• "to fall flat": To fail completely to achieve the intended effect, especially to be unsuccessful in amusing people.

  • His attempt at humor fell flat with the serious audience.

• "flat out":

  • At top speed or with maximum effort: She was working flat out to finish the project.
  • Directly and emphatically: He told me flat out that he was leaving.

• "flat broke": Having no money at all.

  • After paying all the bills, I was flat broke.

Variants and Related Words

• Flatten (verb): To make or become flat.

  • He used a hammer to flatten the piece of metal.

• Flatly (adverb): In an unemotional, definite, or firm manner.

  • She flatly denied all the accusations.

• Flatmate (noun, British English): A person with whom one shares a flat/apartment.

  • My flatmate and I split the rent.

Synonyms

• Adjective: Level, even, smooth, stale, monotonous, absolute, lowered (musical).
• Noun: Apartment, suite, plain, deflation (of a tire).
• Adverb: Absolutely, directly, completely.

Related Phrasal Verbs

• Flat out: As described in 'Advanced Usage'.
• Level off/out: To become flat or steady after rising or falling.
  • The road levels out after this steep hill.

Related Idioms

• "That's flat!": Used to emphasize that a decision or statement is final and will not change.

  • I'm not going, and that's flat!

• "In a flat spin": In a state of panic or confusion.

  • The bad news sent the whole office into a flat spin.

Adjective

1. commercially inactive
   • flat sales for the month
   • prices remained flat
   • a flat market
2. not reflecting light; not glossy
   • flat wall paint
   • a photograph with a matte finish
3. lacking the expected range or depth; not designed to give an illusion or depth
   • a film with two-dimensional characters
   • a flat two-dimensional painting
4. horizontally level
   • a flat roof
5. sounded or spoken in a tone unvarying in pitch
   • the owl's faint monotonous hooting
6. having lost effervescence
   • flat beer
   • a flat cola
7. lacking stimulating characteristics; uninteresting
   • a bland little drama
   • a flat joke
8. lacking taste or flavor or tang
   • a bland diet
   • insipid hospital food
   • flavorless supermarket tomatoes
   • vapid beer
   • vapid tea
9. flattened laterally along the whole length (e.g., certain leafstalks or flatfishes)
10. (of a musical note) lowered in pitch by one chromatic semitone
    • B flat
11. lacking contrast or shading between tones
12. stretched out and lying at full length along the ground
    • found himself lying flat on the floor
13. not modified or restricted by reservations
    • a categorical denial
    • a flat refusal
14. having a relatively broad surface in relation to depth or thickness
    • flat computer monitors
15. having a surface without slope, tilt in which no part is higher or lower than another
    • a flat desk
    • acres of level farmland
    • a plane surface
    • skirts sewn with fine flat seams

Noun

1. a suite of rooms usually on one floor of an apartment house
2. scenery consisting of a wooden frame covered with painted canvas; part of a stage setting
3. a deflated pneumatic tire
4. freight car without permanent sides or roof
5. a musical notation indicating one half step lower than the note named
6. a shallow box in which seedlings are started
7. a level tract of land
   • the salt flats of Utah

Adverb

1. in a forthright manner; candidly or frankly
   • he didn't answer directly
   • told me straight out
   • came out flat for less work and more pay
2. with flat sails
   • sail flat against the wind