IDK
Sayy-dee-KAYUS/ˌaɪ di ˈkeɪ/UK/ˌaɪ diː ˈkeɪ/
- 1Initialism of I don't know.
IDK whether she's still planning to come tonight.
He replied with a quick IDK and changed the subject.
Note
A shorthand born in Internet chat and text messages, and best kept there rather than in formal writing. It is more than a one-word reply: it can stand in for subject and verb and take a clause after it, as in IDK what you're talking about. The full phrase I don't know does wider work too. It can hedge a guess, sarcastically state the obvious, or, in British use, voice exasperation.
Use it in a sentence
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