The Collaborative International Dictionary
Periphrastic conjugation
Periphrastic \Per`i*phras"tic\, Periphrastical \Per`i*phras"tic*al\, a. [Gr. ?: cf. F. p['e]riphrastique.] Expressing, or expressed, in more words than are necessary; characterized by periphrase; circumlocutory.
Periphrastic conjugation (Gram.), a conjugation formed by the use of the simple verb with one or more auxiliaries.
Wiktionary
periphrastic conjugation
n. (context grammar English) conjugation formed by the use of the simple verb with one or more auxiliary