Definition of high-mettled:
(adj) :
Physically elevated, extending above a base or average level:
(adj) :
Very elevated; extending or being far above a base; tall; lofty.
(adj) :
Relatively elevated; rising or raised above the average or normal level from which elevation is measured.
(adj) :
(baseball, of a ball) Above the batter's shoulders.
(adj) :
Pertaining to (or, especially of a language: spoken in) in an area which is at a greater elevation, for example more mountainous, than other regions.
(adj) :
Having a specified elevation or height; tall.