• a leading dignitary of the Roman Catholic Church. Cardinals are nominated by the Pope, and form the Sacred College which elects succeeding popes (now invariably from among their own number)

• a New World songbird of the bunting family, having a stout bill and typically a conspicuous crest. The male is partly or mostly red in colour

• of the greatest importance; fundamental

Synonyms: fundamental, basic, main, chief, primary, prime, principal, premier, first, leading, capital, paramount, pre-eminent