The phenomenon where a member of the opposite sex (or same sex for homosexuals) seems increasingly attractive due to a lack of attractive people within certain surroundings.
For example, while at work one may begin to think that the girl sitting two cubes over is hot, when in all actuality she is not. This perception of hotness is based solely on the fact that she is the only female in the office under 60 and/or under 300 lbs. Outside of the office, she would not stand a chance to an actual hot or cute girl.
Dude, relative hotness is kicking in bad.. I wouldn't mind gettin' a piece of that big girl on the other end of the conference room table.