Synonyms for Mettlesome:

adj.

brave (adjective)
valiant, spunky, spirited, fiery, gritty, peppery, ardent.
energetic (adjective)
snappy, spunky, mighty, fervid, peppy, zippy, ardent, effervescent, active, spirited, forceful, strong, energetic, potent, driven, vigorous, puissant, vivacious, powerful, zealous.
feisty (adjective)
zestful, Gutty.
gritty (adjective)
hardy.
lively (adjective)
active, brisk, animated, alert, vital, lively, enthusiastic, vigorous.
strong (adjective)
robust, virile, sturdy, strong, brawny, energetic, vital, tough, muscular, mighty, powerful, vigorous, stable, stout, potent, firm, sinewy, formidable, husky.
vigorous (adjective)
energetic, agitated, frisky, ardent, earnest, afire, powerful, impassioned, active, vigorous, prolific, ablaze, potent, exuberant, strong, emphatic, excited, industrious, passionate, fervent, fiery, strenuous, zippy, lively, eager, peppy, spirited, enthusiastic, zestful, zealous, puissant, full-blooded, animated, sprightly, virile, lusty, hearty, burning.

n.

fear, valorous, dauntless, gutsy, gallant, stouthearted, unafraid, valiant, doughty, bold, Fortitudinous, Gutty, intrepid, undaunted, hardy, heroic, audacious. feelings, high-spirited, vibrant, peppery, action. gallant (noun)
dauntless, valiant.
mettlesome (noun)
fearless, gamy, game, spunky, gritty, spirited, courageous, gamey, brave.

Other synonyms:

Fortitudinous, valiant, unafraid, gutsy, Gutty, stouthearted, doughty. heroic, dauntless, intrepid, audacious, gallant, valorous, undaunted, vibrant. bold, high-spirited. peppery. hardy. Other relevant words:
gritty, fearless, high-spirited, heroic, peppery, undaunted, dauntless, valorous, doughty, intrepid, unafraid, gallant, Fortitudinous, valiant, bold, stouthearted, gamey, Gutty, courageous, game, vibrant, brave, audacious, gutsy, hardy, gamy.

Usage examples for mettlesome

  1. But Aminta can smell powder and grow more mettlesome – The Complete Project Gutenberg Works of George Meredith by George Meredith
  2. Thine to be lord of the mettlesome chargers, Thine to be lord of swift ships as they wing! – A Victor of Salamis by William Stearns Davis