/ ˌklæsɪfɪˈkeɪʃn; NAmE / noun
1.
[ U ] the act or process of putting people or things into a group or class (= of classifying them) :
a style of music that defies classification (= is like no other)
2.
[ C ] a group, class, division, etc. into which sb or sth is put
3.
[ U ] ( biology ) the act of putting animals, plants, etc. into groups, classes or divisions according to their characteristics
4.
[ C ] ( technical ) a system of arranging books, tapes, magazines, etc. in a library into groups according to their subject