The 'There' turned out to be crucial for the sense of brisance and closure and resolving issues of impotent rage and powerless fear that like accrued in Lenz all day being trapped in the northeastern portions of a squalid halfway house all day fearing for his life, Lenz felt.
-- David Foster Wallace, Infinite Jest
But this was sustained explosion, reaching now and then a quite unendurable brisance. Yet he endured it, not so much because it was her will as, unbelievably, what had become her need.
-- Thomas Pynchon, Against the Day
Brisance is a relatively new English word. It started being used commonly in the 1910s, but it can be traced to the Celtic word brissim meaning "to break."