In modern usage, an orgy is a sex party consisting of at least five members where guests freely engage in open and unrestrained sexual activity or group sex.

Swingers' parties do not always conform to this designation, because at many swinger parties the sexual partners may all know each other or at least have some commonality among economic class, educational attainment or other shared attributes. Some swingers contend that an orgy, as opposed to a sex party, requires some anonymity of sexual partners in complete sexual abandon. Other kinds of "sex party" may fare less well with this labeling.

Participation in an "orgy" is a common sexual fantasy, and group sex targeting such consumers is a subgenre in pornographic films.

The term is also used metaphorically in expressions, such as an "orgy of colour" or an "orgy of destruction" to indicate excess, overabundance. The term "orgiastic" does not generally connote group sex and is closer to the classical roots and this metaphorical usage.