transitive verb

1. to raise (the head, ears, etc.) briskly or spiritedly: often with up
2. to make jaunty or smart in appearance: often with up or out
3. to give or restore freshness, vivacity, etc. to: usually with up

Etymology: ME perken < ? NormFr perquer, var. of OFr percher, perch

intransitive verb

1. to lift one's head, straighten one's posture, etc. jauntily
2. to become lively or animated; esp., to recover one's spirits: with up

adjective

transitive verb, intransitive verb

noun