These words all refer in a negative way to having, expressing or arousing sexual desire. Lewd is the most general of these and the most negative in tone. It can equally well suggest having sexual desires, acting on them or arousing them. Used of a person, it implies thoroughgoing immorality: lewd soldiers on the town. Used of thoughts or feelings, it implies coarseness of sexual appetite, untinged by affection, tenderness or love, but it does not necessarily imply action: lewd glances at every passing woman. Used of literature or art, it implies pornographic or obscene qualities: lewd graffiti on the hoardings. Used of behaviour, it may be considerably weaker, connoting only a provocative or suggestive seductiveness: the lewd poses of the chorus girls.

Licentious and wanton emphasize the active satisfaction of desire, although neither word is restricted in meaning to sexual impulse alone. Licentious can suggest any kind of excessive freedom in behaviour that goes past legal or moral bounds or violates customary standards of behaviour: a licentious attitude towards premarital affairs. Wanton , by contrast, does not suggest extreme freedom so much as unruly or wasteful self-indulgence. Used of people or people’s behaviour it suggests sensuality more than sexuality: the wanton , fast-living film colony. Only in its sense of gratuitous does it suggest extreme inhumanity or cruelty: wanton slaughter.

Lustful and lecherous may suggest unacted-upon desire as well as the active seeking of satisfaction: a lecherous mood; a lustful disposition. Lustful suggests a permanent character trait not likely to remain unexpressed, while lecherous can be used to refer to a momentary desire for a particular person: goaded by lecherous feelings for his new secretary. Neither of these words is likely to be used for pornographic materials, designed to arouse desire.

Lascivious and prurient , unlike the other words here, tend to be restricted more specifically to having sexual desire than to acting upon it. Both words are commonly used to describe the feelings that pornography in particular is intended to incite, with prurient being the word favoured in legal terminology: whether a book taken as a whole arouses prurient interests in the average person and is utterly without redeeming social importance. Lascivious is milder and stresses inclination, whereas prurient stresses susceptibility.

Salacious , alone of these words, most usually suggests the material intended to incite sexual fantasies or desires: salacious movies shown at smokos.

In general, sexual impulses per se are not so widely disapproved of a formerly, and a present-day view of what should be classified as lewd and what as zestful high spirits would differ drastically from a 19th-century view.