Cross-dressing involves wearing clothing traditionally associated with a different gender than one's own. In fetish contexts, this may be done for erotic pleasure, as part of roleplay, or for personal expression.
The practice exists separately from gender identity - many cross-dressers are cisgender and heterosexual, engaging with the practice for various reasons including erotic excitement, stress relief, aesthetic appreciation, or exploring different aspects of self.
In BDSM contexts, cross-dressing may be incorporated as forced feminization or masculinization, where a dominant directs the submissive to dress in specific ways. The power exchange adds another dimension to the practice.
Related terms include transvestism (clinical term), forced feminization (in BDSM), and drag (performance art). Each has distinct connotations and contexts.