adjective, plain·er, plain·est.


clearly and simply: He's just plain stupid.


an area of land not significantly higher than adjacent areas and with relatively minor differences in elevation, commonly less than 500 feet (150 meters), within the area.
The Plains. Great Plains.

Nearby words

  1. plaguy,
  2. plaice,
  3. plaid,
  4. plaid cymru,
  5. plaided,
  6. plain as day,
  7. plain bearing,
  8. plain chocolate,
  9. plain clothes,
  10. plain dealing

Origin of plain

1250–1300; Middle English (adj., adv., and noun) < Old French (adj. and noun) < Latin plānus flat, level, plānum flat country

Related formsplain·ly, adverbplain·ness, noun

Can be confusedplain plan plane

Synonym study

10. See homely. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for plainly

British Dictionary definitions for plainly




flat or smooth; level
not complicated; clearthe plain truth
not difficult; simple or easya plain task
honest or straightforward
lowly, esp in social rank or education
without adornment or showa plain coat
(of fabric) without pattern or of simple untwilled weave
not attractive
not mixed; simpleplain vodka
knitting of or done in plain


a level or almost level tract of country, esp an extensive treeless region
a simple stitch in knitting made by putting the right needle into a loop on the left needle, passing the wool round the right needle, and pulling it through the loop, thus forming a new loop
(in billiards)
  1. the unmarked white ball, as distinguished from the spot balls
  2. the player using this ball
(in Ireland) short for plain porter, a light portertwo pints of plain, please


(intensifier)just plain tired
See also plains

Derived Formsplainly, adverbplainness, noun

Word Origin for plain

C13: from Old French: simple, from Latin plānus level, distinct, clear




a dialect or poetic word for complain

Word Origin for plain

C14 pleignen, from Old French plaindre to lament, from Latin plangere to beat

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for plainly
Online Etymology Dictionary, © 2010 Douglas Harper

Science definitions for plainly



An extensive, relatively level area of land. Plains are present on all continents except Antarctica and are most often located in the interior regions. Because they can occur at almost any altitude or latitude, plains can be humid and forested, semiarid and grass-covered, or arid.
A broad, level expanse, such as an area of the sea floor or a lunar mare.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Idioms and Phrases with plainly


In addition to the idioms beginning with plain

  • plain as day
  • plain sailing

also see:

  • in plain English
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.