mid-14c., roundeaboute, "by a circuitous route," also "on all sides, all about," from round (adv.), for which see round (adj.), + about. As an adjective, "in a ring or circle," by mid-14c. By late 15c. (Caxton) as a preposition. As an adjective from c. 1600. Noun sense of "traffic circle" is attested from 1927. It was used earlier of other things, such as "circular course or object" (1530s), "a plump, rounded figure" (1812), "a detour" (1755), "a merry-go-round" (1763). Related: Roundaboutness.
c. 1300, "in circumference, in a circle, on every side," from phrase on round; see a- (1) + round (adj.). Rare before 1600. In sense of "here and there with no fixed direction" it is attested from 1776 in American English (British English prefers about). As a preposition, "on or along a circuit," late 14c.; "on all sides, encircling, about" 1660s; of time, by 1873. To have been around "gained worldly experience" is from 1927, U.S. colloquial; to get around to it is from 1864.
"about, at or near (a given date)" when the exact time is unknown, 1856, from Latin circa (adv., prep.) "around, round about, near; in the region of; about the time of," alternative form of circum "round about" (see circum-).
mid-15c., Peripatetik, "a disciple of Aristotle, one of the set of philosophers who followed the teachings of Aristotle," from Old French perypatetique (14c.) and directly from Medieval Latin peripateticus "pertaining to the disciples or philosophy of Aristotle," from Greek peripatētikos "given to walking about" (especially while teaching), from peripatein "walk up and down, walk about," from peri "around, about" (see peri-) + patein "to walk, tread" (see find (v.)). Aristotle's custom was to teach while strolling through the Lyceum in Athens.
In English, the philosophical meaning is older than that of "person who wanders about" (1610s). As an adjective, "walking about from place to place, itinerant," from 1640s, often with a tinge of humor. Related: Peripatetical.