2 meanings: 1. the activity embracing all forms of the purchase and sale of goods and services 2. social relations and.... Click for more definitions. Definition of commerce noun in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. business, commerce, trade, industry, traffic mean activity concerned with the supplying and distribution of commodities. business may be an inclusive term but specifically designates the activities of those engaged in the purchase or sale of commodities or in related financial transactions. Learn what commerce is, its meaning, types, and importance in business. Check how commerce drives trade, economic growth, and global transactions in today's interconnected world.