know what's what


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know what's what

To know the true facts or most fundamental information (about someone or something). Kid, I've been doing this job for longer than you've been alive, so trust me when I say that I know what's what around here.
See also: know, what

know what's what

if you know what's what, you have a lot of experience and can judge people and situations well Harry's been in the business for 40 years - he knows what's what.
See also: know, what