J-Crewin it Share definition Flag If your J-Crewin it your not in sweats, but your not dressed up. Also,when your J-Crewin it you can't have jeans on, you must have khakis or nicer on. Bob:"You look nice today"Sally:"Not really, I'm just J-crewin it.Bob:"Oh, ........OK. J-Crewin it by Mado1243 December 14, 2009 Get the J-Crewin it mug.