the most noble three branches of the Tokugawa clan (徳(とく)川(がわ)氏(し) (Tokugawa-shi)): 尾張(おわり) (Owari), 紀伊(きい) (Kī), and 水戸(みと) (Mito) / (figuratively) the "big three"

a female given name

author of hentai (pornographic manga)

(geometry, mathematics) Euclidean geometry

auditory phonetics

(phonetics) articulatory phonetics

microbiology

(mathematics) geometrical

(mathematics) calculus, infinitesimal calculus

(anthropology) ethnography - the branch of anthropology that scientifically describes specific human cultures and societies.