carry on (v.)

1640s, "continue to advance," also "manage, be engaged in," from carry (v.) + on (adv.). Meaning "conduct oneself in a wild and thoughtless manner" is by 1828. Carryings-on is from 1660s as "questionable doings," from 1866 as "riotous behavior." As an adjective, carry-on, in reference to luggage that may be brought into the passenger compartment of an airliner, by 1965.