1) A physical state generally describing increased heart rate and body temp.

2) Describing when a person has begun feel the effects of drinking alcohol, or a warm up, prior to an activity.

3) Describing an indoor restroom which has just been used or simply reeks of shit.

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.