A man's penis, specifically in the erect position.
My mantenna is detecting some estrogen in the area, so I should follow it to find the girl of my dreams.
by Marcus Solomon October 30, 2007
the male penis... but unlike many antennas, this mantenna can only be used properly by a female... unless your gay.
"Oooo... look at the mantenna go up!"
by D&J November 15, 2002