Aaron Donald Shows Off Ripped Abs In Shirtless Selfie During Rams Holdout

Aaron Donald sent a message to the Rams on Thursday -- six of them, in fact -- letting his abs say the words his mouth didn't ... PAY ME!!

The not-so-subtle memo to his L.A. bosses went down on Donald's IG ... where the superstar D-lineman -- who's still holding out -- posed shirtless with every one of his six abs flashing.

The caption might as well have had general manager Les Snead's name on it too ... 'cause it read, "Lookin good for 280."

Translation -- he's a 6"1', 280-pound monster in incredible shape ready to get back on the football field.