A discrete item is an item of language isolated from context.
Examples of discrete items could be a single phoneme such as /e/, the past form -ed, a phrasal verb such as 'get up', or a conjunction such as 'in addition'.
In the classroom
A discrete item approach to teaching language isolates the language and enables teachers and learners to focus on the item itself. For example, it is often useful to practise sounds as discrete items, then in words and connected speech. Discrete items often appear in testing, where there is a need to focus on knowledge of specific items.