bigswanger Share definition Flag a term used to describe the size of one's genitals. often used by a man who is overcompensating for having very small genitals. He bragged about being a bigswanger even though his manhood was quite small. bigswanger by seanperrytx May 1, 2007 0 0 Get merch Get the bigswanger mug. Buy Now — $32.95 See more merch