principal adjective [ always before noun ] uk/ˈprɪnsəpəl/ us B1 main, or most important
главный, основной Her principal reason for moving is to be nearer her mother. principal noun [ C ] uk/ˈprɪnsəpəl/ us B2 the person in charge of a school or college
директор (школы, колледжа) She was caught smoking and sent to see the principal .