perk (v.)

"rod or pole on which a bird alights and rests," late 13c., originally only "a pole, rod, stick, stake," from Old French perche "unit of linear measurement" (5.5 yards), also "measuring rod, pole, bar" used to measure this length (13c.), from Latin pertica "pole, long staff, measuring rod," which is related to Oscan perek "pole," Umbrian perkaf "twigs, rods." Meaning "a bar fixed horizontally for a hawk or tame bird to rest on" is attested from late 14c.; this led to the general sense of "any thing that any bird alights or rests on" (late 15c.). Figurative sense of "an elevated or secure position" is recorded from 1520s.

1620s, "to strain through" (transitive), a back-formation from percolation, or else from Latin percolatus, past participle of percolare "to strain through." Figurative sense by 1670s. Intransitive sense of "to pass through small interstices" is from 1680s. Related: Percolated; percolating.