Definition of precious adjective in Oxford Advanced Learner's Dictionary. Meaning , pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. precious meaning , definition , what is precious : something that is precious is valuable a...: Learn more. Learn the English definition and meaning of Precious with examples, pronunciation, and translations to enhance your vocabulary. Learn the meaning of precious as an adjective and an adverb, with examples and synonyms. Find out how to use precious to describe rare, valuable, loved, or pleasing things or qualities.