the ability or driving force of an individual to persevere when they think they can't go any farther.
man, I was about to throw it in during that last round, but then I got a huge dose of mettle.
by p!ss3d 0Ff Ho++ Sh!T March 05, 2009
Ability to persevere despite obstacles...usually performed with class or grace.
Cambria showed her mettle when the bowling alley dude informed her that the metal roller business was broken.
by jd33_33 November 11, 2012