Sissy (derived from sister; also sissy baby, sissy boy, etc.) is a pejorative term for a boy or man who violates or does not meet the standard male gender role. Generally, sissy implies a lack of courage and stoicism, which are thought important to the male role. A man might also be considered a sissy for being interested in traditional feminine hobbies or employment (e.g., being fond of fashion), displaying effeminate behavior (e.g., saying “mua mua” before hanging up the phone or using creams), being unathletic, or being homosexual.
Sissy is, approximately, the male converse of tomboy (a girl with masculine traits or interests), but has none of the latter’s positive connotations. Even amongst gay men, behavior thought of as sissy or camp produces mixed reactions. Some men reclaim the term for themselves.
The term sissyphobia denotes a negative cultural reaction against “sissy boys” thought prevalent in 1974. Sissyphobia has more recently been used in some queer studies; other authors in this latter area have proposed effeminiphobia as an alternative term.
Sissy (or sis) can also be a relationship nickname formed from sister, given to girls to indicate their role in the family, especially the oldest female sibling. It can also be applied to girls as a term of affection from friends who are not family members. (See Sissy Spacek.)
Communication Scholar, Shinsuke Eguchi (2011) defines that:
"The discourse of straight-acting produces and reproduces anti-femininity and homophobia(Clarkson. 2006). For example, feminine gay men are often labeled “fem,”“bitchy,” “pissy,” “sissy,” or “queen” (e.g., Christian, 2005; Clarkson, 2006; Payne,2007). They are perceived as if they perform like “women,” spurring straight-acting gay men to have negative attitudes toward gay feminine men (Clarkson, 2006; Payne, 2007;Ward, 2000). This is called sissyphobia (Bergling, 2001). Kimmel (1996) supports that “masculinity has been (historically) defined as the flight from women and the repudiation of femininity” (p. 123). Thus, sissyphobia plays as the communication strategy for straight-acting gay men to justify and empower their masculinity." (p. 38).
Eguchi (2011) continues to say, “I wonder how “sissyphobia” particularly plays into the dynamic of domestic violence processes in the straight-acting and effeminate-acting male same-sex coupling pattern” (p. 53).