late 14c., "formal authorization, official permission, permit, privilege," from Old French licence "freedom, liberty, power, possibility; permission," (12c.), from Latin licentia "freedom, liberty; unrestrained liberty, wantonness, presumption," from licentem (nominative licens), present participle of licere "to be allowed, be lawful," from PIE root *leik- "to offer, bargain, make a bid" (possibly source also of Lettish likstu "I come to terms").
Meaning "formal (usually written) permission from authority to do something" (marry, hunt, drive, etc.) is first attested early 15c. Meaning "excessive liberty, disregard of propriety" in English is from mid-15c. In Middle English spelled licence, licens, lisence, lissens, licance. There have been attempts to confine license to verbal use and licence to noun use (compare advise/advice, devise/device, and see note in OED); in the U.S., license tends to serve as both verb and noun.
Poetic licence "intentional deviation from recognized form or rule" is from 1733, earlier as lycence poetycall (1530). The licence-plate is from 1870 (of dogs and wagons before automobiles); licence-number is by 1903.
"the art or practice of trying to catch fish," c. 1300, fysschynge, verbal noun from fish (v.). Figurative use from 1540s. The Old English noun was fiscað.
[O]f all diversions which ingenuity ever devised for the relief of idleness, fishing is the worst qualified to amuse a man who is at once indolent and impatient. [Scott, "Waverly," 1814]
Fishing-boat is from 1732. Fishing rod (1550s) is older than fishing pole (1791). To "go fishing" is as old as Old English on fiscoð gan.
"morally unrestrained," 1530s, from Medieval Latin licentiosus "full of licence, unrestrained," from Latin licentia "freedom, liberty," in both a good and bad sense (see licence (n.)). Related: Licentiously; licentiousness.
"written statement of permission or licence, written authority to do something," 1714, from permit (v.).