Green’s Dictionary of Slang

(US) to live as a tramp.

1918		Chicago Sun. Trib. 27 Oct. 2: When I was ‘boin’’ round [...] I met up with a lot o’ ’bos in the northern woods [HDAS].
1929		E. Dahlberg Bottom Dogs 189: That’s what one gets ridin’ the blinds, boeing about. [Ibid.] 206: How long had he been boeing, it appeared ages.