I. noun Date: circa 1705 one's own interests or welfare ; oneself , one that is first in rank, importance, or influence, II. adjective Date: 1839 first in rank, importance, or influence ; foremost , of highest or of high quality
NUMBER ONE
Meaning of NUMBER ONE in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012