diastema [ˌdʌɪəˈstiːmə, dʌɪˈastɪmə] (pl. diastemata)
a gap between the teeth, in particular 齿隙,尤指 ■(Zoology)a space separating teeth of different functions, especially that between the biting teeth (incisors and canines) and grinding teeth (premolars and molars) in rodents and ungulates (动)齿隙,牙间隙 ■a gap between a person's two upper front teeth (人的)上门齿间的间隙
语源
mid 19th cent.: via late Latin from Greek diastema space between'