Mettlesome
Pronunciation : Met"tle*some
Part of Speech : a.
Definition : Defn: Full of spirit; possessing constitutional ardor; fiery; as, a mettlesome horse. -- Met"tle*some*ly, adv. -- Met"tle*some*ness, n.
Source : Webster's Unabridged Dictionary, 1913
Merriam-Webster's Everyday Language Reference Set: Includes: The Merriam-Webster Dictionary, The Merriam-Webster Thesaurus, and The Merriam-Webster Vocabulary Builder