monosexual Share definition Flag A person who's sexual prefernce is one sex. It can be heterosexual or homosexual. Lisa is a monosexual lesbian and does not like men, therefore she's not bisexual. monosexual by R·D January 1, 2004 Words you can keep railfan mug chonk mug chud mug based mug 67 mug slime mug mogging mug chopped mug thot mug glazing mug huzz mug yams mug larp mug unc mug cracked mug simp mug baddie mug bop mug lolcow mug