Medigoron

Biggoron's younger brother of a size smaller than Biggoron but still larger than your average Goron. Medigoron claims to be as good as his brother as smithing, and asks Link to pay 200 rupees in exchange for the Giant's Knife, a blade which turns out to be essentially useless as it breaks shortly after you use it. Medigoron appears in Ocarina of Time.

He also appears in Majora's Mask, this time making the devastating Powder Keg. He is also the Goron that gives Link his Powder Keg Certification, a certificate proving he knows how to use the Powder Kegs.

Medigoron's name seems to be a portmanteau of medi- (from the latin medius, meaning middle), and -goron (believed to originate from the phrase "goron, goron", a Japanese onomatopoeia for the sound of a rolling rock.)