Icebag is a (male) masturbatory technique in which a ziploc baggie is filled with ice or ice water. When one is pleasuring himself, the cold bag is held against the testicles. Many proponents of this technique claim that it increases both the intensity of the orgasm and the amount of semen ejected from the body.
Date didn't go well last night so I went home and decided it was time for an icebag. Good choice on my part.