An ELT Glossary : Notions

Notions are described by Wilkins (1976) as "semantico-grammatical" categories - ie the categories of meanings and concepts that are needed in order to communicate. They include  such categories as time, quantity and location, each of which can be broken down into subcategories. Time, for instance, includes the subcategory of Time Duration, expressed linguistically by prepositional phrases : for five years, until Tuesday, since Monday etc

Notions were one of the three types of meaning that were used in the work of the Council of Europe's work on syllabus design, published in the early seventies - the others being functions and modal meaning -  and which form the basis of syllabus design in the early Communicative Approach - though it was undoubtedly the concept of function which was most emphasised,

See also : Notional-Functional Syllabuses

Reference

Wilkins, D.A, 1976, Notional Syllabuses, OUP