A sexual term meaning to help your partner or partner's penis back into the girl.

From STEM, an abbreviation short for "Science, Technology, Engineering and Mathematics", a STEMlord is a pejorative term for a particular kind of person who has studied in these areas at university or works in these fields who holds a pretentious, condescending attitude to anyone who has studied in any other fields, particularly the Arts and Humanities. They typically believe themselves to be more "intelligent" and "rational", while generally remaining incredibly ignorant outside of their areas of expertise and having the charisma of a rotting pig's backside.

When you and your buddy are smashing the same girl, your buddy slips out accidently so you reach over and lift up his dick to help him continue.

A sex position when you left a girl up and destroy her.