[Greek thumos, excrescence like a thyme bud, thymus gland.]
The thymus is a gland in the neck which produces T-lymphocytes for the immune system. A thymocyte (Greek kutos, vessel) is a lymphocyte within the gland; a thymoma is a rare, usually benign tumour arising from thymus tissue; thymectomy (Greek ektomē, excision) is surgical removal of the thymus gland. The usual adjective referring to the thymus or its functions is thymic. Thymine is one of the four constituent bases of nucleic acids, so named because a related compound was first extracted from the thymus.