Meaning of weak ending

weak' end'ing

Pronunciation: [key]
— Pros. Pros.
  1. a verse ending in which the metrical stress falls on a word or syllable that would not be stressed in natural utterance, as a preposition, the object of which is carried over to the next line.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.