Heterosexism
Around the same time, heterosexism began to be used as a term analogous to sexism and racism, describing an ideological system that denies, denigrates, and stigmatizes any nonheterosexual form of behavior, identity, relationship, or community (Herek, 1990). Using the term heterosexism highlights the parallels between antigay sentiment and other forms of prejudice, such as racism, antisemitism, and sexism.
Like institutional racism and sexism, heterosexism pervades societal customs and institutions. It operates through a dual process of invisibility and attack. Homosexuality usually remains culturally invisible; when people who engage in homosexual behavior or who are identified as homosexual become visible, they are subject to attack by society.
Examples of heterosexism in the United States include the continuing ban against lesbian and gay military personnel; widespread lack of legal protection from antigay discrimination in employment, housing, and services; hostility to lesbian and gay committed relationships, recently dramatized by passage of federal and state laws against same-gender marriage; and the existence of sodomy laws in more than one-third of the states.
Although usage of the two words has not been uniform, homophobia has typically been employed to describe individual antigay attitudes and behaviors whereas heterosexism has referred to societal-level ideologies and patterns of institutionalized oppression of non-heterosexual people.