SINCE 1828
I don't know
idiomDefinition of I don't know
1
—used to say that one does not have the information someone is asking for "What time does the library close?" "I don't know."
2
informal
—used to express disagreement, doubt, or uncertainty "I don't like that guy." "Oh, I don't know, he's not really so bad."She thinks we should go now, but I don't know. Maybe we should wait.
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