who knows what

who knows what

One or more things described with no detail. Our junk drawer has old remotes, instruction manuals, and who knows what else in it. You're supposed to be doing your homework, but instead you're slacking off and doing who knows what!
See also: know, what, who
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

who knows what

see under what have you.
See also: know, what, who
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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References in periodicals archive ?
In 1 Corinthians we read, "Among human beings, who knows what pertains to a person except the spirit of the person that is within?