Gabro or Gabbro: How To spell?

The word Gabro is misspelled against Gabbro, a noun meaning "A name originally given by the Italians to a kind of serpentine, later to the rock called euphotide, and now generally used for a coarsely crystalline, igneous rock consisting of lamellar pyroxene (diallage) and labradorite, with sometimes chrysolite (olivine gabbro)."