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plain

adj. · n. · adv.
US //ˈpɫeɪn// UK //plˈeɪn// plain
  1. 1 simple or undecorated (adj.)
    B1 Intermediate

    simple and not decorated with patterns or extra details.

    lacking ornament, decoration, or pattern; simple in design or appearance.

    Example

    He wore a plain white t-shirt and blue jeans to the party.

    Example

    The interior was decorated in a plain, minimalist style that emphasised the architectural lines of the building rather than the furniture.
  2. 2 easy to understand (adj.)
    B1 Intermediate

    clear and easy to see or understand.

    clear to the mind; easy to perceive or understand without ambiguity.

    Example

    The truth was plain to see for everyone in the room.

    Example

    The instructions were written in plain English to ensure that users without technical backgrounds could operate the machinery safely.
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  1. 3 not attractive (adj.)
    B2 Upper Intermediate

    not beautiful or handsome, but not ugly either.

    not distinguished by beauty; having a simple or unremarkable appearance.

    Example

    She described herself as a plain person who didn't like wearing makeup.

    Example

    The protagonist was often described as a plain woman, a choice by the author to focus on her intellectual depth rather than her physical appearance.
  2. 4 flat land (n.)
    B1 Intermediate

    a large area of flat land with few trees.

    an extensive area of level or gently undulating land, usually at a low elevation and often covered in grass.

    Example

    The train travelled across the vast plains for several hours.

    Example

    The Great Plains of North America support a diverse ecosystem despite the relatively low annual rainfall and lack of natural forest cover.
  3. 5 completely or simply (adv.)
    B2 Upper Intermediate Informal

    used to emphasize that something is completely true or simple.

    used as an intensifier to mean 'simply' or 'completely'; typically precedes an adjective.

    Example

    That idea is just plain stupid.

    Example

    It was plain wrong of him to take credit for work that the entire team had contributed to over the last six months.

    Usage

    Usually placed before an adjective to add emphasis.
Etymology 1

From Middle English pleyn, borrowed from Anglo-Norman pleyn, playn, Middle French plain, plein, and Old French plain, from Latin plānus (“flat, even, level, plain”). Doublet of llano, piano, and plane.

Etymology 2

From Old French plain, from Latin plānum (“level ground, a plain”), neuter substantive from plānus (“level, even, flat”). Doublet of llano, piano, and plane.

Etymology 3

From Anglo-Norman plainer, pleiner, variant of Anglo-Norman and Old French pleindre, plaindre, from Latin plangere.

Etymology 4

From Middle English pleyn, borrowed from Old French plein, from Latin plēnus (“full, filled, complete”). Ultimately from Proto-Italic plēnos, from Proto-Indo-European pl̥h₁nós (“full”). Doublet of plene, plenary, and full.

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Idioms3 entries

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