Somebody who stands in a pose at the sides or back of a gig or party, stroking their chin in a misguided attempt to appear being disaffectedly engaged in and/or disapproving of the music currently being played.
Don't bother trying to get across to the bar over there, that entire corner of the room is infested with chinstrokers
Fogey/fogy /fougi/ sl. (early 18C+, orig. Scot) old-fashioned, stuck-in-the mud.
Person with old fashioned ideas which he is unwilling to change: Come to the disco and stop being such an old fogey!
You think me an old fogeyand an old tory, his thoughtful voice said. I saw three generations since O’Connel’s time. I remember the famine. Do you know that the orange lodges agitated for repeal of the union twenty years before O’Connel did or before the prelates of your communion denounced him as a demagogue? You fenians forget some things. (James Joyce, Ulysses. PenguinBooks,1992. p. 38)