Dictionary
1number one
noun
: a person, thing, or position that is highest in rank : the most important person or thing in a group of people or things
: the most successful person or thing in a group of people or things
: your own happiness, health, or success
Full Definition of NUMBER ONE
1
: one's own interests or welfare : oneself <looking out for number one> —often written No. 1
2
: one that is first in rank, importance, or influence —often written No. 1
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First Known Use of NUMBER ONE
circa 1705
2number one
adjective
: highest in rank or importance
Full Definition of NUMBER ONE
1
: first in rank, importance, or influence : foremost <cancer is the country's number one killer> —often written No. 1
2
: of highest or of high quality
See number one defined for English-language learners
First Known Use of NUMBER ONE
1839
Related to NUMBER ONE
- Synonyms
- arch, big, capital, cardinal, central, chief, dominant, first, grand, great, greatest, highest, key, leading, main, master, foremost (also No. 1), numero uno, overbearing, overmastering, overriding, paramount, predominant, preeminent, premier, primal, primary, principal, prior, sovereign (also sovran), supreme
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