The word has syntactic and semantic properties as well as a morphological structure, and is therefore available as the interface of these different patterns. The notion of morpheme is used, but only as an element of form: "[f]eature values are assigned to words on the basis of their internal strusture" [...]. Thus there is no need to assume that morphemes have constant syntactic or semantic properties, because the mapping between the two is mediated by the word.
- Creider & Hudson (2004), a pag.447