Found 2 items, similar to mettlesomeness.
English → English (WordNet) Definition: mettlesomeness mettlesomeness n : courageous high-spiritedness
English → English (gcide) Definition: Mettlesomeness Mettlesome \Met"tle*some\, a. Full of spirit; possessing constitutional ardor; fiery; as, a mettlesome horse. [1913 Webster] -- Met"tle*some*ly, adv. -- Met"tle*some*ness, n. [1913 Webster]