1) Hair disease 
Hypotrichosis (hypo- + tricho- + -osis) is a condition of abnormal hair patterns - predominantly loss or reduction. It occurs, most frequently, by the growth of vellus hair in areas of the body that normally produce terminal hair. Typically, the individual`s hair growth is normal after birth, but shortly thereafter the hair is shed and replaced w....
hairlessness
Sparse coat.
Presence of less than the normal amount of hair. ... (12 Dec 1998) ... 
(hi″po-trĭ-ko´sis) presence of less than the normal amount of hair; see also alopecia.
Type: Term Pronunciation: hī′pō-tri-kō′sis Definitions: 1. A less than normal amount of hair on the head and/or body. Synonyms: hypotrichiasis1, oligotrichia, oligotrichosis
Condition characterized by a sparse hair coat.
hypotrichosis 1. Congenital deficiency or sparsity of hair. 2. Diminished growth of hair.