homo- (2) Look up homo- at Dictionary.com
word-forming element meaning "homosexual," abstracted since early 20c. from homosexual, and ultimately identical to homo- (1).
homo- (1) Look up homo- at Dictionary.com
before vowels hom-, word-forming element meaning "same, the same, equal, like" (opposed to hetero-), from Greek homos "one and the same," also "belonging to two or more jointly," from PIE *somo-, from root *sem- (1) "as one; together with" (see same).