a person who only has sexual relations with women that have birthed offspring.
wait, didn't she just have a kid like a month ago? you mother f'er...
by Benny March 29, 2004
Another way of saying "Mother F*cker."
That mother f*cker stole my food!
by Shervin Mobasseri March 30, 2004
More polite way of saying mother fucker
I dislike that mother f'er.
by me March 30, 2004
One who has sex with their wife/girlfriend after the said party has already had at least one child.
After having sex with my wife last night, I am now a mother f'er.
by Dave March 30, 2004