WordNet (r) 3.0 (2006):
perk up v 1: gain or regain energy; "I picked up after a nap" [syn: perk up, perk, percolate, pick up, gain vigor] 2: cause to be alert and energetic; "Coffee and tea stimulate me"; "This herbal infusion doesn't stimulate" [syn: stimulate, arouse, brace, energize, energise, perk up] [ant: calm, de-energise, de-energize, sedate, tranquilize, tranquillise, tranquillize]