Definition of "metonymical"

Meander is a Riuer in Lycia, a Prouince of Natolia, or Aſia minor famous for the ſinuoſitie and often turning thereof, riſing from certaine hills in Meonia, hereupon are intricate turnings by a tranſumptive and metonimicall kind of ſpeech, called Meanders, for this Riuer did ſo ſtrangely path it ſelfe, that the foote ſeemed to touch the head.

1597, Michaell Draiton [i.e., Michael Drayton], “[Englands Heroicall Epistles.] The Epistle of Rosamond to King Henry the Second. Notes of the Chronicle Historie.”, in Poems: […], London: […] [Valentine Simmes] for N[icholas] Ling, published 1605, folios 4, verso – 5, recto