classifier

noun5

1. •
   Someone who classifies.

   • He was a model of anal defensiveness: fastidious in his dress and appearance, a collector and putter of things in order, a classifier and labeler. — 1995
2. •
   A machine that separates particles or objects of different size or density.
3. •
   A program or algorithm that classifies.
4. •
   A word or morpheme used in some languages (such as CJKV languages and sign languages), in certain contexts (such as counting), to indicate the semantic class to which something belongs.
5. •
   A metaclass used to group other entities having common features.

   • A classifier can have several types of extra information attached to it via a UML mechanism called adornments. — 2005