Wikipedia
Homohysteria is the fear of being thought homosexual because of behavior that is typically considered gender atypical. Homohysteria can exist in cultures where it is understood that people are and can be homosexual, even if closeted, and that homosexuality is perceived as less desirable than heterosexuality. This combination leads to men fearing others will think they are gay if they do not fit male gender stereotypes. Not fitting into gender stereotypes (gender atypicality) has historically been associated with gay men, with the trials of Oscar Wilde furthering this belief in Britain and elsewhere, with his conviction of gross indecency furthering public stereotypes about gay males. Because of these misconceptions, many stereotypically "masculine-acting" gay men were exempt from public suspicion about their sexuality.