What is the medical term for head lice infestation?

The medical term for head lice infestation is "Pediculosis capitis." This term specifically refers to the presence of lice on the scalp and hair, which is characterized by itching and discomfort. Understanding this terminology is crucial in the context of identifying and treating infestations, as lice are parasitic insects that feed on human blood and can lead to secondary infections due to excessive scratching.

The other terms provided represent different conditions: scabies refers to a contagious skin condition caused by mite infestation. Dermatitis is a general term for inflammation of the skin with various causes, including allergies and irritants. Onychomycosis describes a fungal infection of the nails. Each term is distinct in its implication and treatment approach, which emphasizes the importance of using the correct medical terminology in practice.