From Longman Dictionary of Contemporary Englishmature market/industrymature market/industrytechnical a mature industry or market is one where growth is quite low and there are fewer competitors than before → mature
Examples from the Corpus
mature market/industry• Here on the Island we have a mature market.• The propane industry was a mature industry and Mega was primarily a single business company.• And there are other more mature markets in which our business can be expanded further.• Price competition Price competition occurs in mature markets, much of it induced by clients.• It is, rather, a mature market that is in decline.