From Longman Dictionary of Contemporary Englishkey ringˈkey ring noun [countable] 
Da metal ring that you keep keys on
Da metal ring that you keep keys onExamples from the Corpus
key ring• Sebastian Nocon got a huge key ring with the letter S on it from Fergie.• He had to fumble in it for some seconds before his fingers found the key ring.• Other good features include a spare bulb in the tail cap and a useful key ring facility.• She rummaged in her handbag for the key on its wooden key ring and tried to fit it into the lock. 