Categorisation is a task where learners have to put language into different categories.

Example
Learners categorise conjunctions according to their function.

In the classroom
Examples of activities include categorising words according to type, e.g. verb, noun, preposition; categorising functions, e.g. request, order, suggestion; categorising vocabulary by negative or positive.

Further links:

https://www.teachingenglish.org.uk/article/vocabulary-activities

https://www.teachingenglish.org.uk/article/snack-facts-recording-vocabulary