emperor noun
ADJ. reigning
VERB + EMPEROR crown sb Charlemagne was crowned Emperor on Christmas Day 800 AD.
PREP. under an/the ~ It was under the emperor Justinian that these advances were made. | ~ of the emperor of Japan
PHRASES the reign of an emperor during the reign of the last emperor
You can also check other dicts: emperor (English, 中文解释 ), wordnet sense, Collins Definition