celluloid /ˈsɛljəˌloɪd/ noun Learner's definition of CELLULOID
[noncount]
1
: a tough kind of plastic that was used in the past to make photographic film and other products赛璐珞（过去用于制作电影胶片和其他产品）
2
: the film used to make movies（拍电影用的）胶片 —
often used before another noun to refer to movies in general常用于另一名词前，泛指电影