a dace is someone who makes you /facepalm
if someone is being annoying, dumb, mean, selfish, or any negative adjective, they are a dace.
may or may not originate from the japanese word "desu", meaning "is". although this would neither make sense considering its sound or meaning, please consider that the originator of this term was, in fact, a dace.
dude #2: you, my friend, are a dace
bro #1: i only listen to indie music, i'm an interesting person
bro #2: you.... are the dace of spades.
person #1: dude YOU'RE SO GAY
person #2: and you're a dace