Looking for a way to highlight cells that contain a specific word as part of a bigger word

Hey gang, got a sheet with several thousand cells with chunks of text in em (a paragraph or so of "issue description" type text). I'm looking for a way to highlight cells that contain a specific word as part of a bigger word.

eg - I'm looking for the word "sign". I want every cell that has a word that contains the word sign to be highlighted (consign, design, designate, etc etc).

My googling has lead me nowhere so I've come to the real pros for help