Classifier

Noun

1. Someone who classifies.
2. A word or morpheme used in some languages (such as CJKV languages and American Sign Language), in certain contexts (such as counting), to indicate the semantic class to which something belongs.
3. A machine that separates particles or objects of different size or density.
4. A program or algorithm that classifies.
5. A metaclass used to group other entities having common features.