undefined

undefined — adjective

1. describing something that is stated or known only in a way that is unclear, impr

1.形容詞B2
釋義

describing something that is stated or known only in a way that is unclear, imprecise, or open to different interpretations — for example, a role with no fixed duties, or a boundary that has not been drawn exactly.

例句

The exact boundaries of the park remain undefined in the city's planning documents.

remain undefined + location phrase

When Élise joined the team, her main responsibilities were still undefined by the manager.

passive: be + undefined by [person]

同義詞
  • vague

    focuses on lack of precision rather than absence of boundaries; less formal

  • ambiguous

    means open to multiple interpretations, not just unclear

  • unclear

    more general and neutral; the simplest synonym

反義詞
  • defined

    the direct opposite; clearly stated or described

  • clear

    obvious and easy to understand

  • specific

    exact and detailed

用法筆記

Common in formal and written English. Frequently used with verbs like 'remain,' 'leave,' or 'stay.'

常見錯誤

❌The rules are indefinite about overtime.
✅The rules are undefined about overtime.
💡'indefinite' means a period with no end; 'undefined' means not clearly stated.

2. lacking a formal statement of its meaning or value; without an explicit definiti

2.形容詞B2
釋義

lacking a formal statement of its meaning or value; without an explicit definition in a system where one is normally expected — for example, a term in a technical paper with no glossary entry, or a variable in computer code that has not been assigned a value.

例句

The compiler reported an error because the variable 'count' was left undefined in the code.

technical: left undefined in [code/system]

Terms like 'cognitive load' and 'working memory' were left undefined in Dr. Okafor's paper, confusing many readers.

同義詞
  • unspecified

    means not named or mentioned, not necessarily lacking a definition

  • unstated

    means not expressed in words; softer than 'undefined'

反義詞

用法筆記

Particularly common in computing, mathematics, and lexicography, where formal definitions are expected. In programming, 'undefined' often causes errors at compile time or runtime.

常見錯誤

❌ 'The law left the crime undefined, so no one was charged.' (The sentence is structurally fine, but 'undefined' in legal contexts more commonly means 'not legally defined' — which is correct here.) This is actually correct usage.