'perk up' definitions:

Definition of 'perk up'

(from WordNet)
verb
Gain or regain energy; "I picked up after a nap" [syn: perk up, perk, percolate, pick up, gain vigor]
verb
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]