morphasexual Share definition Flag Someone who's sexual nature and/or orientation changes. Someone who has more than one mode of sexual nature and/or orientation. The person's morphasexual nature allowed zim to be straight at some times and gay at other times. morphasexual by Ophir September 22, 2005 0 0 Get merch Get the morphasexual mug. Buy Now — $32.95 See more merch