We found one dictionary that defines the word prove mettle:

Miscellaneous (1 matching dictionary)

1. prove mettle: Idioms

▸ Words similar to prove mettle ▸ Usage examples for prove mettle ▸ Idioms related to prove mettle ▸ Wikipedia articles (New!) ▸ Words that often appear near prove mettle ▸ Rhymes of prove mettle ▸ Invented words related to prove mettle