Sexual dysfunction refers to a sexual disorder in which the patient (client) finds it difficult to function adequately while having sex.
Other definition:
Sexual dysfunction refers to an abnormality in a person's sexual responsiveness and reactions.It also refers to a disturbance of sexual functioning
Other /More definition:
Sexual Dysfunction refers to a class of sexual disorders characterized by inhibitions in sexual desire or the psychophysiologic changes that characterize the sexual response cycle.
Likewise, Sexual Dysfunction is an impairments in sexual functioning that causes subjective distress.