don't-know

American  

[dohnt-noh] / ˈdoʊntˈnoʊ /

noun

1. a person who has no opinion or is undecided, as in answering an item on a public-opinion poll.

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don't know British  

noun

1. a person who has not reached a definite opinion on a subject, esp as a response to a questionnaire

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Etymology

Origin of don't-know

First recorded in 1885–90

Example Sentences

Though a Daily Telegraph Gallup poll reported last week that 46% of Britons will support Britain's Common Market membership if it is in the nation's best interest�a gain of 2% since the Commonwealth Prime Ministers' conference last month�Labor believes that the anti-Marketeers will ultimately include the 24% don't-know vote.

From Time Magazine Archive

You are like 'John Don't-know' in the fairy tale.

From Project Gutenberg