A sexual euphemism used by homosexuals in reference to anal sex.

A device inserted into the anus to measure the temperature of the human body.
Example: 1)
Leslie: <lisp> I think I have a fever. </lisp>

Weslie: <lisp> Let's have a look see. I'll whip out my "rectal thermometer". </lisp>

Leslie: <lisp> OHHHHH GOOODIE I was hoping you'd say that!!!!</lisp>

Weslie: <lisp>Ohhhh...I think I have a fever. </lisp>

Leslie: <lisp> ALRIGHT!!! It's my turn to whip out the ‘ol "rectal thermometer". </lisp>

Weslie: <lisp>No, I'm not feeling well; I need the real rectal thermometer! </lisp>

Leslie: <lisp>DAMN!!!! </lisp>
by fagsRgay January 13, 2009
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The act of sticking a digit into your female partners anus, while engaging in intercourse, in order to gauge that womans boundries or limitations concerning further action, up the old dirt road.
Clint: "Yo Dan, why you got a black eye man?"
Dan: "Yo, Michel socked me in the eye-face after I gave her a Rectal Thremometer. I guess I won't find out how pink her sock is."
Clint: "Awe fo' real doh?"
Dan: "Naw, billdo."
by Dan Jewell February 24, 2005
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