A contemporary version of the old expression, "don't let the bastards get you down," this version stands for "don't let the motherfuckers get you down." The mofos are generally anyone in authority or authority figures, whether bosses, family members, partners etc.
"I hate my job. The boss asked to clean the bathroom."
"He's a jerk. Don't let the mofos get you down."
"He's a jerk. Don't let the mofos get you down."
by kingharvest November 5, 2009
Get the don't let the mofos get you downmug.