ˈbɹaɪni tʃiːf ɪndɪˈpɛndənt ˈpɹaɪməɹi ˈpɹaɪməɹi ˈpɹɒeməɹi ˈpɹɪnsɪpəl (of a clause) capable of standing syntactically alone as a complete sentence the main (or independent) clause in a complex sentence has at least a subject and a verb most important element the chief aim of living the main doors were of solid glass the principal rivers of America the principal example policemen were primary targets the master bedroom a master switch of force; of the greatest possible intensity by main strength a principal pipe in a system that distributes water or gas or electricity or that collects sewage any very large body of (salt) water