undefined

adjective

un·​de·​fined ˌən-di-ˈfīnd 

: not defined: such as

a

: not clearly or precisely shown, described, or limited

undefined rules

undefined powers

a vague, undefined feeling of dread

… the true outlines of Clinton's foreign policy remain undefined.

—William Greider

b

: not provided with a definition

an undefined dictionary entry

Synonyms of undefined

• vague
• faint

Examples of undefined in a Sentence

plagued by undefined worries that kept her awake at night

Recent Examples on the Web

Residents were caught in a liminal space where loss and grief are undefined. — Matthew Carey, Deadline, 8 Nov. 2026

So executives do what any capable leader does with an undefined assignment. — Leslie Ellis, Forbes.com, 6 Nov. 2026

Artificial intelligence is big, scary, exciting and more than just a little undefined. — Evan Clark, Footwear News, 28 Oct. 2026

Still, several categories in New York's law are broadly worded or undefined, Gluck said. — ABC News, 28 Oct. 2026

Word History

First Known Use

1611, in the meaning defined above

Rhymes for undefined

• aligned
• alined
• assigned
• behind
• combined
• confined
• consigned
• crosswind
• declined
• defined
• designed
• divined