buzz (n.)

"a busy rumour" [Rowe], 1620s (earlier "a fancy," c. 1600), figurative use from buzz (v.). Literal sense of "a humming sound" is from 1640s. A "buzz" was the characteristic sound of an airplane in early 20c.; hence verbal sense "to fly swiftly," by 1928; by 1940 especially in military use, "to fly low over a surface as a warning signal" (for example that target practice is about to begin):
The patrol aircraft shall employ the method of warning known as "buzzing" which consists of low flight by the airplane and repeated opening and closing of the throttle. [1941 Supplement to the Code of Federal Regulations of the United States of America," Chap. II, Corps of Engineers, War Department, p. 3434, etc. ]
Meaning "pleasant sense of intoxication" first recorded 1935. The children's game of counting off with 7 or multiples of it replaced by buzz is attested from 1864 and is mentioned in "Little Women" (1868). To give (someone) a buzz (by 1922) is from the buzz that announced a call on old telephone systems (1913). Buzz bomb "V1 rocket" is from 1944.

buzz (v.)

late 15c. (buzzing is from late 14c.), echoic of bees and other insects. Aviation sense of "fly low and close" is by 1941 (see buzz (n.)). Related: Buzzed. To buzz off "go away quickly" (1914) originally meant "to ring off on the telephone," from the use of buzzers to signal a call or message on old systems. As a command, it originally would have been telling someone to get off the line.