The interpretation of the slashed categories is as follows: A/B is the category of expressions combining with an element of category B immediately to their right, to form a constituent of category A. Similarly, A \ B is the category assigned to the elements which take an expression of category A to their left in order to form a constituent of category B. The slashed categories of the first type will be called "rightward-looking functors", or, in more familiar terminology, "prefixes", and the slashed categories of the second type "leftward-looking functors", or "suffixes".
- Hoeksma (2004), Pag. 198-199