1. A name given to two species of grouse in which the male has spiky tail and olive-green air sacs, more like man boobs
The males, the sage cocks, compete with each other by showing off their moobs, to the amazement of the female sage grouse. The females are picky about whose moobs are best, and usually only the fittest, most dominant male is successful.
2. Someone who thrusts their arms and moobs in a similar manner to a sage grouse, in hopes of attracting lots of women. It turns out to be ineffective compared to the birds.
1. "Yo check out this video on YouTube it's a bird with man boobs, the sage grouse!"
Female sage grouse: "Oh wow, look at his spiky tail and moobs, it's so hot!"
2. "Stop showing your moobs, you sage grouse! You won't get any girls!"