Etymologically

flat

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English has two words spelled flat: “level”, from Old Norse, and the apartment, an alteration of Scots flet, from Old English; the two are related.[1][2][3]

Pronunciation

  • IPA: /flæt/[4]

flat1 level

Etymology

The level is inherited from Middle English flat,[5] borrowed from Old Norse flatr (“flat”),[6][1][2][7] from Proto-Germanic *flataz,[2] which is also the source of Old Saxon flat “flat, shallow” and Old High German flaz “flat, level”,[6][1][5] from Proto-Indo-European *plat- (“to spread”),[6] the root also of Greek platýs “flat, broad” and Latvian plañdît “to make broad”.[1][5] Hoad calls the Germanic word of uncertain origin.[2] It is related to place and plate.[1][5]

Earliest recorded meaning

Stretched out, prostrate, lying at full length: about 1300 in Etymonline[6] and Barnhart,[1] and about 1320 in the OED.[8] The noun “level ground” is in place names from 1167, as Kirkeflat.[1][6]

Semantic evolution

“Level, all in one plane, even” is from the mid-14th century, and “without curvature” from about 1400.[6][8] Of a building levelled with the ground it is from 1560.[8] “Prosaic, dull”, from the notion of featureless, is from the 1570s,[6] and of drink from about 1600.[6] Of musical notes, lower than the intended pitch, it is from the 1590s,[6] first recorded in Shakespeare's Two Gentlemen of Verona (1594);[1] the flat sign and the natural sign are modified forms of the letter b.[6] The adverb “absolutely, downright” is from the 1550s.[6] A flat surface, as of a sword, is from the late 14th century, and a low shoe from 1834.[6] The flat tyre is from 1908,[6] flat-earth from 1876,[6] and flat out, first in motor racing, from 1932.[6] To flatline, to die, after the straight line on a heart monitor, dates from the 1970s.[3]

Timeline

  • 1167 – the place name Kirkeflat.[1]
  • c. 1300 – prostrate.[6][1]
  • mid-14th century – level, even.[6]
  • 1550s – adverb, absolutely.[6]
  • 1570s – dull.[6]
  • 1594 – of a musical note.[1]
  • c. 1600 – of drink.[6]
  • 1908 – flat tyre.[6]
  • 1932 – flat out.[6]

Modern meaning

Adjective

  1. Having a level surface without slope or curve.
  2. Smooth and even.
  3. Broad and thin.
  4. Lying at full length; prostrate.
  5. Dull and lifeless; of a drink, no longer fizzy.
  6. Fixed; unvarying: a flat rate.
  7. Of a tyre, deflated.
  8. In music, lower than the correct pitch, or a semitone lower than the natural note.

Adverb

  1. Level with the ground; at full length.
  2. Directly; completely: flat broke.
  3. Exactly: in ten seconds flat.

Noun

  1. A flat surface or part.
  2. A stretch of level ground, often by water.
  3. A deflated tyre.
  4. In music, a flat note, or the sign ♭.

Word family

  • flatly
  • flatness
  • flatten
  • flattish
  • flatfish
  • flatfoot
  • flatboat
  • flatcar
  • flatiron
  • flatline

flat2 apartment

Etymology

The apartment is inherited from Scots flet (“floor or storey of a house, inner part of a house”),[1][2] altered by association with flat “level”,[2] inherited from Middle English flet (“room, hall”),[1] inherited from Old English flett (“a dwelling, hall; floor, ground”),[6][1] from Proto-Germanic *flatjam,[6][2] a derivative of *flataz “flat”,[2] from Proto-Indo-European *plat- (“to spread”).[6] Old Saxon flet “room, house” and Old High German flezzi “floor” are cognates.[1]

Earliest recorded meaning

A floor or storey of a house: 1801, Scottish,[1][8][6] with the Old English word for a dwelling or floor going back to about 725, in Beowulf.[1]

Semantic evolution

A set of rooms on one floor, forming a residence, is first recorded in Scott's Redgauntlet (1824).[1][8][6] The word is chiefly British,[1][9] and Americans say apartment.[10]

Timeline

  • c. 725 – Old English flett, in Beowulf.[1]
  • 1801 – a storey.[1][8]
  • 1824 – an apartment.[1][8]

Modern meaning

Noun

  1. (chiefly British) A set of rooms on one floor forming a home; an apartment.

Word family

  • flatmate
  • flatlet

References

  1. ^ a b c d e f g h i j k l m n o p q r s t u v Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
  2. ^ a b c d e f g h Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
  3. ^ a b Cresswell, Julia (2021), Oxford Dictionary of Word Origins, 3rd ed., Oxford: Oxford University Press
  4. ^ Jones, Daniel (2011), Cambridge English Pronouncing Dictionary, 18th ed., ed. Peter Roach, Jane Setter and John Esling, Cambridge: Cambridge University Press
  5. ^ a b c d Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
  6. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z 27 Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  7. ^ Pearsall, Judy, ed. (1998), The New Oxford Dictionary of English, Oxford: Clarendon Press
  8. ^ a b c d e f g Simpson, J. A.; Weiner, E. S. C., eds. (1989), The Oxford English Dictionary, 2nd ed., Oxford: Clarendon Press
  9. ^ Collins English Dictionary (2023), Glasgow: HarperCollins
  10. ^ The American Heritage Dictionary of the English Language (1992), 3rd ed., Boston: Houghton Mifflin