The rules for the 6th version of Wounded keep it together read
6. When you are confronted by the horrendous, supernatural, or mind-shattering, roll+Steady. On a 10+ you take -1 the next time you keep it together. On a 7-9 you gain a break or wound a move. On a 6-you black out, the GM will describe what unfortunate circumstances you wake up in.
In this context what is a "break"? It's not mentioned anywhere else in the rules as far as I can tell.