\On*cot"o*my\ ([o^][ng]"k[o^]t*[-o]*m[y^]), n. [Gr.
'o`gkos bulk, mass + te`mnein to cut: cf. F. oncotomie.]
(Surg.)
The opening of an abscess, or the removal of a tumor, with a
cutting instrument. [Written also {onkotomy}.] --Dunglison.