Puto or puta is a derogatory spanish word for achillean men and transfeminine people, more commonly for gay men. It is often translated as "homo" [1], however, a literal translation would be prostitue or rentboy [2]. This follows the homophobic tradition of equating homosexuality with promiscuity.
Reclaming
Although the term is generally pretty offensive and it's still commonly use in a derogatory way, it is not impossible to find it being reclaimed in a similar fashion to f*ggot or d*ckgirl. [3]