Dictionary.com
Thesaurus.com
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:

They’re hiding in plain sight, as ordinary people who run businesses woven into the fabric of everyday life.

From The Wall Street Journal Sep. 4, 2026

Such trends were in plain sight in Tor Bella Monaca, a working-class eastern suburb of Rome dotted by rundown apartment blocks, cash-for-gold shops and discount stores.

From Barron's Sep. 2, 2026

One group received plain water, while the other two received water containing either sucralose or stevia.

From Science Daily Aug. 31, 2026

It hasn't all been plain sailing - already two councillors, Steve Lewis and Rhys Carr, have left Reform to sit as independents, and a third, Nick Farmer, has been suspended by the party.

From BBC Aug. 27, 2026

I’m not sure if it’s because of adrenaline or just plain bad decision-making, but I decide I’m not going to let this thing beat us.

From "Kwame Crashes the Underworld" by Craig Kofi Farmer

Water can take about a day to reach the Bihar plains from the Nepal mountain front along the Kosi and Gandak, and somewhat longer along the Ghaghara.

From BBC Sep. 3, 2026

Deep-sea mining companies want to scour the ocean's abyssal plains for mineral deposits and polymetallic nodules laden with nickel, copper and cobalt.

From Barron's Aug. 6, 2026

It is essential for cattlemen in the western plains who have for years been shrinking their cattle herds in response to droughts.

From The Wall Street Journal Jul. 11, 2026

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

When a scouting party spotted a herd, Ne-kah-e-se-y and the other hunters raced on their horses across the plains, the hooves pounding the earth like drums, the manes whipping the riders’ sweating, gleaming faces.

From "Killers of the Flower Moon" by David Grann

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

The male peacocks have the extravagant plumage to attract mates, while the females are a plainer colour.

From BBC Aug. 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

We can’t put it any plainer than he does: These assaults “are a direct result of multiple systems’ lack of appropriate resources, placements, and services” for kids in dire need.

From Seattle Times Nov. 29, 2023

It could not have been plainer that he thought this lesson was a waste of time.

From "Harry Potter and the Half-Blood Prince" by J.K. Rowling

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

I had picked up a book about adventurous greens, only to fall for the plainest one.

From Salon May 26, 2025

He said this in just the plainest everyday voice, as if discussing that the dog had gotten into the garbage again.

From "The Poisonwood Bible" by Barbara Kingsolver

Vocabulary.com logo
by dictionary.com
Image

Join 12,000,000 vocabulary learners

Start learning new words today on VocabTrainer.
You'll remember them forever.

Start training