1. fashionable; in style ⇒ Such would-be with-it phrases only get used in TV advertisements when they are no longer fashionable., ⇒ a with-it young man, ⇒ fashion magazines trying to be with it
2. comprehending what is happening or being said ⇒ Tell her to get with it., ⇒ I'm not with it today., ⇒ Sorry, didn't mean to leave that info out. I'm not with it today., ⇒ She wasn't really with it. She hadn't taken in the practical consequences.
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