periphrasis

In linguistics, periphrasis is a device by which grammatical meaning is expressed by one or more free morphemes (typically one or more function words accompanying a content word), instead of by inflectional affixes or derivation. Periphrastic forms are analytic, whereas the absence of periphrasis is a characteristic of synthesis. While periphrasis concerns all categories of syntax, it is most visible with verb catenae. The verb catenae of English are highly periphrastic.