The Collaborative International Dictionary
Whinner
Whinner \Whin"ner\, v. i. To whinny. [Colloq.]
Douglas Harper's Etymology Dictionary
whinner
"to whine feebly," c.1700, frequentative of whine. Related: Whinnered; whinnering.
Wiktionary
whinner
vb. (context colloquial intransitive English) To whinny.