caliber

Concise Oxford English Dictionary © 2008 Oxford University Press:
calibre /ˈkalɪbə/ (US caliber)

▶noun

• 1 quality of character or level of ability.

  ■ the standard reached by something.

• 2 the internal diameter of a gun barrel.

  ■ the diameter of a bullet, shell, or rocket.

– derivatives
calibred adjective.

– origin C16 (in the sense ‘social standing’): from Fr., from Ital. calibro, perh. from Arab. ḳālib ‘mould’.