Dactylic: an ictosyllabic form of metre in which each beat (see prosody) is typically followed by two offbeats (a combination traditionally called a dactyl). In “The Charge of the Light Brigade” Tennyson uses dactyls to suggest the gallop of the horses (the last line is catalectic [see catalexis]):
* . . | * . .
Cannon to |right of them,