Both Uses of

vagrant
in
In Cold Blood

I was really enjoying myself till a man came along and arrested me for vagrancy.†
Chpt 2 *

But he was not isolated, there were people to talk to, a plentiful turnover of drunkards, forgers, wife-beaters, and Mexican vagrants; and Dick, with his light-hearted "con-man" patter, his sex anecdotes and gamy jokes, was popular with the inmates (though there was one who had no use for him whatever-an old man who hissed at him: "Killer!†
Chpt 4

vagrants = people who are poor and have no regular home or job

Definitions:

(1) (vagrant)
someone who is poor and has no regular home or job
(2) (meaning too rare to warrant focus)
meaning too rare to warrant focus:

Less commonly, and especially long ago, you may see vagrant used to emphasize that a poor person wanders from place to place. Even more rarely, it can describe an animal as being in a place it usually is not, or to describe anything that varies or seems random such as the seeming haphazard direction in which a certain weed spreads, or the fleeting quality of something smelled for only an instant.