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Synonyms

plain

1 American  
[pleyn] / pleɪn /

adjective

plainer, comparative plainest superlative
  1. clear or distinct to the eye or ear: to stand in plain view.

    a plain trail to the river;

    to stand in plain view.

    Synonyms:
    perspicuous, apparent, unmistakable, intelligible, understandable, lucid
    Antonyms:
    indistinct
  2. clear to the mind; evident, manifest, or obvious.

    to make one's meaning plain.

    Synonyms:
    transparent, patent, unequivocal, unambiguous, perspicuous, apparent, unmistakable, intelligible, understandable, lucid
    Antonyms:
    obscure
  3. conveying the meaning clearly and simply; easily understood.

    plain talk.

    Synonyms:
    transparent, patent, unequivocal, unambiguous
  4. downright; sheer; utter; self-evident.

    plain folly;

    plain stupidity.

  5. free from ambiguity or evasion; candid; outspoken.

    the plain truth of the matter.

    Synonyms:
    sincere, open, ingenuous, frank, blunt, direct, straightforward, unreserved
  6. without special pretensions, superiority, elegance, etc.; ordinary.

    plain people.

    Synonyms:
    unpretentious
  7. not beautiful; physically unattractive or undistinguished.

    a plain face.

  8. without intricacies or difficulties.

  9. ordinary, simple, or unostentatious.

    Although she was a duchess, her manners were attractively plain.

  10. with little or no embellishment, decoration, or enhancing elaboration.

    a plain blue suit.

  11. without a pattern, figure, or device.

    a plain fabric.

  12. not rich, highly seasoned, or elaborately prepared, as food.

    a plain diet.

  13. flat or level.

    plain country.

    Antonyms:
    hilly
  14. unobstructed, clear, or open, as ground, a space, etc.

  15. Cards. being other than a face card or a trump.


adverb

  1. clearly and simply.

    He's just plain stupid.

noun

plains plural
  1. 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.

  2. The Plains. Great Plains.

idioms

  1. in plain sight. see in plain sight.

plain 2 American  
[pleyn] / pleɪn /

verb (used without object)

British Dialect.
  1. to complain.


plain 1 British  
/ pleɪn /

verb

  1. a dialect or poetic word for complain

"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

plain 2 British  
/ pleɪn /

adjective

  1. flat or smooth; level

  2. not complicated; clear

    the plain truth

  3. not difficult; simple or easy

    a plain task

  4. honest or straightforward

  5. lowly, esp in social rank or education

  6. without adornment or show

    a plain coat

  7. (of fabric) without pattern or of simple untwilled weave

  8. not attractive

  9. not mixed; simple

    plain vodka

  10. knitting of or done in plain

"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

noun

  1. a level or almost level tract of country, esp an extensive treeless region

  2. 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

    1. the unmarked white ball, as distinguished from the spot balls

    2. the player using this ball

  3. (in Ireland) short for plain porter, a light porter

    two pints of plain, please

"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

adverb

  1. (intensifier)

    just plain tired

"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
plain Scientific  
/ plān /
  1. 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.

  2. A broad, level expanse, such as an area of the sea floor or a lunar mare.


plain More Idioms  

    More idioms and phrases containing plain


Synonym Usage

See homely.

Other Word Forms

Derived Forms

Inflected Forms

Nouns

Adjectives

Etymology

Origin of plain1

First recorded in 1300–50; Middle English adjective, adverb, and noun plain(e), plein(e), from Old French adjective and noun plain(e), pleine, from Latin plānus “flat, level,” plānum “flat country”

Origin of plain2

First recorded in 1250–1300; Middle English plei(g)nen, plene(n), from Anglo-French plainer, pleiner, Old French plaign-, stem of plaindre, pleindre, from Latin plangere “to strike, beat (the breast, etc.), lament”

Explanation

Plain things are simple, unadorned, and even a little boring. Being a plain talker means you don't use pretentious, fancy words. But having a plain face means you're not much to look at. Plain comes from the Latin word planum, meaning "level ground." That's one meaning of the word, as in a flat prairie or low lying coastal flood plain. If something is in plain view, it's out in the open with no obstructions. But usually we use plain as an adjective to describe unembellished, bare, or unimpressive things. A white room with just an old bed and a chair is pretty plain.

Keep Reading on Vocabulary.com

Vocabulary lists containing plain

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Whether or not Argentina lifts the trophy again, the lesson is already out on the field in plain sight every time Messi touches the ball.

From Salon Jul. 15, 2026

Langer’s charges $24 for a plain hot-pastrami sandwich, while New York’s Katz’s Delicatessen charges $28.95.

From Los Angeles Times Jul. 13, 2026

Most plain corn chips should therefore be considered minimally processed, because they take almost no processing to make.

From Slate Jul. 12, 2026

In plain and punchy prose, he at times rebuked his fellow justices for not showing sufficient deference to the president.

From The Wall Street Journal Jul. 10, 2026

A second Gestapo agent in plain clothes was pawing eagerly through a pile of silver rijksdaalders and jewelry heaped on the dining room table.

From "The Hiding Place" by Corrie ten Boom

Priyadarshini said she has long been interested in studying spiders that live at high elevations because those environments differ greatly from the lowland plains in both vegetation and landscape.

From Science Daily Jul. 9, 2026

“Little House on the Prairie” is the third television adaptation to bear the name of Laura Ingalls Wilder’s 1935 autobiographical novel of life on the Kansas plains in 1869 to 1870.

From Los Angeles Times Jul. 9, 2026

"If we don't protect the Aravalli, the northern Gangetic plains -- which is a food basket for the rest of the country -- would become a desert," he said.

From Barron's May 31, 2026

Coronado also inadvertently shaped the course of Native American plains culture when Puebloans captured some of his horses.

From The Wall Street Journal Apr. 28, 2026

In winter the wind of the plains may keep the city clear of snow, but when it blizzards and piles up they do not clear the streets, having no streets to clear.

From "The Left Hand of Darkness" by Ursula K. Le Guin

He is also often being asked how to zhuzh up plainer fare or find satiety with smaller portions.

From The Wall Street Journal Jul. 16, 2026

His brother Andy, who makes up the final third of the band on drums, it was even plainer than that.

From BBC Feb. 5, 2025

In plainer English, Cannon chided prosecutors for rushing to file the gag order just before the Memorial Day weekend.

From Salon May 28, 2024

For example, Chinese zhajiangmian is usually plainer than Korean-Chinese jajangmyeon, which is coated in a thick sauce of fermented black beans.

From Los Angeles Times Jan. 26, 2024

It made her seem plainer, and her face was made up in pale colors that weren’t flattering either.

From "Code Name Verity" by Elizabeth Wein

In “Love and Summer,” William Trevor’s novel of doomed romance and quiet resignation, even the plainest sentence conveys roiling emotion.

From The Wall Street Journal Mar. 9, 2026

Mr Duck KC said: "It was the plainest of intrusions and the fear it caused was inevitable."

From BBC Oct. 7, 2025

In plainest English: If the people with the heaviest vehicles made do with slightly less, the impact to the safety of their lives would be literally zero, and thousands fewer people would die.

From Slate Jun. 22, 2025

Brushing ahead all that geeky frippery, though, and what’s plainest about that scene is how unsettling it is.

From Salon Jan. 18, 2025

I fiddle with the curly mass of my bangs and slouch down, feeling like the plainest girl ever next to the fashion plate that is Katherine Deveraux.

From "Dread Nation" by Justina Ireland

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