劍橋詞典

a hard substance containing calcium that forms the main part of a tooth and has enamel (= a shiny white substance ) covering it
象牙質(zhì)（構(gòu)成牙齒主體的堅(jiān)硬含鈣物質(zhì)，表面覆蓋白色牙釉質(zhì)） 返回 dentine