brio (n.) Look up brio at Dictionary.com
"liveliness, vivacity," 1734, from Italian brio, literally "mettle, fire, life," perhaps a shortened derivative of Latin ebrius "drunk." Or via Provençal briu "vigor," from Celtic *brig-o- "strength," from PIE root *gwere- (2) "heavy" (see grave (adj.)). Probably entered English via musical instruction con brio.