informal

/ɪnˈfɔːml/ (bre, ipa) · /ɪnˈfɔːrml/ (ame, ipa) · /(ˌ)in-ˈfȯr-məl/ (ame, mw)

informal — adjective

  • informalpositive
  • more informalcomparative
  • most informalsuperlative

1. Done without following official rules, formal procedures, or accepted customs —

1.形容詞B1
釋義

Done without following official rules, formal procedures, or accepted customs — for example, an informal agreement between friends that is not written down.

例句

Anjali and Ignacio made an informal agreement to share taxi rides to work.

collocation: informal agreement

Ryo's promotion was discussed informally over lunch rather than in a proper meeting.

同義詞
  • unofficial

    Focuses on lack of official recognition; 'unofficial' is often used for rules or reports, while 'informal' is broader.

  • off-the-record

    More specific — describes information not meant to be made public or attributed.

  • unceremonious

    Describes actions done without the expected formalities; slightly more literary.

反義詞
  • official

    The direct opposite; 'official' things follow established rules or procedures.

  • formal

    The broader opposite across both senses; formal events follow strict customs and protocols.

文法句型

informal + noun

be + informal

用法筆記

This sense is frequently used to describe arrangements, systems, or meetings that lack official status or documentation. The opposite is formal.

常見錯誤

❌The meeting was informal, so I had to fill out many forms.
✅The meeting was informal, so no official forms were needed.
💡'informal' means few or no official procedures, not the opposite.
❌He made an informal speech to the president at the state dinner.
✅He made an informal speech to his team during the company picnic.
💡'informal' describes relaxed settings; formal events call for formal behaviour.

2. (Of clothes, language, or behaviour) relaxed and suitable for everyday situation

2.形容詞B1
釋義

(Of clothes, language, or behaviour) relaxed and suitable for everyday situations with people you know, rather than for official or serious events.

例句

For the beach party, Nicholas wore informal clothes like shorts and a simple T-shirt.

collocation: informal clothes

The professor prefers an informal style where students call him by his first name.

collocation: informal style

同義詞
  • casual

    Almost interchangeable for clothing and behaviour; 'casual' is slightly more common for describing dress codes.

  • relaxed

    Focuses on the comfortable, unhurried feeling rather than the absence of rules.

  • friendly

    Describes the warm, welcoming quality of an informal situation between people.

反義詞
  • formal

    The direct opposite — formal dress, language, or behaviour follows strict rules for official occasions.

  • dressy

    Specifically for clothing; dressy clothes are elegant and suitable for special events.

  • stiff

    Describes behaviour or atmosphere that is overly formal and lacking in warmth.

文法句型

informal + noun

be + informal

用法筆記

Commonly appears with nouns describing clothing (informal clothes, informal dress), communication (informal language, informal tone), and settings (informal atmosphere, informal gathering). This sense contrasts with formal and does not imply poor quality or lack of respect.

常見錯誤

❌He speaks informal English, which means his grammar is always wrong.
✅He speaks informal English, meaning he uses casual expressions suitable for talking to friends.
💡'informal' language is not incorrect; it just follows different conventions from formal language.
❌She wore informal dress to the job interview.
✅She wore formal business attire to the job interview.
💡Job interviews are official occasions that usually require formal or at least smart-casual clothing, not informal dress.