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1.
Noun. The potent, and usually putrid, crotch odor that develops after about four days of sustained, strenuous activity without benefit of a bath; the malodorous mixture of testicle and ass sweat. Often associated with multi-day backpacking, biking or climbing trips.
I didn't realize I had mountain junk until I changed my underwear this morning.
by jrw April 28, 2005