What is Inflection?
We encountered inflection in Inflection vs. Derivation, but here we explore it in more detail. The word itself comes from traditional Latin grammar. Its root flect-, which we see in the English word flex, means ‘bend’. (The British and German spelling, inflexion, is even closer to flex.) We give this etymology to evoke the image of a speaker “bending,” or, perhaps more clearly, altering the shape of a word so it will fit in a particular position within a sentence. Every sentence is a syntactic frame with positions for a series of words. In order to fill one of those positions, you take a lexeme from the lexicon and bend it to fit. In this way, inflectional morphology is determined by syntax.
What kinds of things do lexemes express through inflection? In general, we speak of inflection expressing morphosyntactic information, syntactic information that is expressed morphologically. This includes the abstract syntactic categories of tense, aspect, number, and case. Specific values for these categories, such as past, imperfective, plural, or genitive, are generally referred to as morphosyntactic features or morphosyntactic properties, the latter a term from Matthews (1991).
Inflection is the realization of morphosyntactic features through morphological means.
In order to fully understand inflection, we must situate it in the grammar. Since we are claiming that the syntax provides the morphology with morphosyntactic features, the job of the morphology must be to get from there to the actual phonological realization:
This diagram portrays the relationship between the syntax, morphology, and phonology as derivational, but it is equally possible to model a non-derivational, parallel relationship. Either way, a diagram like (1) is bound to be deceptively simple. We are still left asking precisely how words become inflected. We now turn to an exploration of the answers to that question.
