Nasty; low; vicious and deceptive •Also uttered in seven-card stud poker as the last cards are dealt face down: Mississippi: A Down and Dirty Campaign/ This is down-and-dirty time. Just witness Rizzo's angry characterization of Goode(1950s+)
The Dictionary of American Slang, Fourth Edition by Barbara Ann Kipfer, PhD. and Robert L. Chapman, Ph.D. Copyright (C) 2007 by HarperCollins Publishers. Cite This Source
Idioms and Phrases with down and dirty
down and dirty
Vicious, not governed by rules of decency, as in The candidates are getting down and dirty early in the campaign.
[ ; early 1980s
Very earthy, uninhibitedly sexual. For example, “L.A. club people rarely get down and dirty on a dance floor” (The New Yorker, May 21, 1990).
[ Late 1980s