Slang.
This is
old slang for a habitual
thief,
drunkard, or
hustler. Less-commonly used to refer to someone with general
experience, as in "
old-timer". In
poker, a
career player, the
opposite of a "
sucker."
As the
Webster's
definition implies, "rounder" is derived from the phrase "to make the rounds."
Supreme Court Justice
William O. Douglas used the
word in his
biography: " . . .It was a moving, eloquent
plea: he had a
mother to support; he was
poor as a
church mouse; he was not a "rounder" or a "
boozer." Vol. I, p.99. (1974).