number one

noun
UK: /ˌnʌm.bə ˈwʌn/
US: /ˌnʌm.bɚ ˈwʌn/

  1. The best or most important person or thing.

    1. She is number one in my book. [ ] [ ]
    2. My family is always my number one priority, no matter what challenges arise. [ ] [ ]

  2. A popular or successful product.

    1. It's their number one selling item. [ ] [ ]
    2. The new phone model quickly became the company's number one product, exceeding all expectations. [ ] [ ]

  3. To urinate.

    1. The puppy went number one on the rug. [ ] [ ]
    2. I need to go number one before we leave for the long drive, so give me a minute. [ ] [ ]

Synonyms

best leading principal top chief prime
number one intransitive-verb

  1. To urinate.

    1. The baby had to number one. [ ] [ ]
    2. The toddler loudly announced they needed to number one, disrupting the quiet library. [ ] [ ]
number one adjective

  1. Being the most important or best.

    1. She's my number one friend. [ ] [ ]
    2. Solving the climate crisis is our number one global challenge for the future. [ ] [ ]

Frequently Asked Questions

The word "number one" in English means: The best or most important person or thing., A popular or successful product., To urinate..

The phonetic transcription of "number one" is /ˌnʌm.bə ˈwʌn/ in British English and /ˌnʌm.bɚ ˈwʌn/ in American English. Click the 🔊 button to hear both pronunciations.

Synonyms for "number one": best, leading, principal, top, chief, prime.

Example usage of "number one": "She is number one in my book.". More examples on the page.