What term describes an infestation of lice in hairy areas or on clothing?

The term that describes an infestation of lice in hairy areas or on clothing is pediculosis. This condition specifically refers to an infection caused by parasitic lice, which can affect various parts of the body, predominantly the scalp, body, and pubic regions. In cases of pediculosis, the presence of lice leads to symptoms such as itching, irritation, and inflammation in the areas they infest.

The other terms, while related to skin and infestations, do not accurately describe lice infestations. Scabies refers to an infestation by the Sarcoptes scabiei mite, which causes intense itching and skin irritation but is different from lice. Dermatitis is a general term for skin inflammation that can have a variety of causes, but it is not specifically related to lice infestations. Psoriasis is a chronic autoimmune condition characterized by the rapid growth of skin cells leading to thick, red, scaly patches, and it is also unrelated to lice. Thus, pediculosis is the precise term for an infestation involving lice.