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a single person or thing
There is one book on the table.
There is a single book on the table.
Used to refer to a single entity or individual.
a single unit or item
One plus one equals two.
A single unit plus another single unit equals two.
In mathematics, 'one' represents the number 1.
a single instance or occurrence
This is one of the best movies I've seen.
This is a single instance of the best movies I've seen.
Used to indicate a single instance among many.
'One' can be used as a pronoun to avoid repetition, e.g., 'One should always be polite.'
When using 'one' as a pronoun, ensure consistency in gender and number, e.g., 'One should do one's best'.
Old English 'ān', from Proto-Germanic 'ainaz', from Proto-Indo-European 'oi-no-'.
'One' can function as a pronoun, determiner, or noun. As a pronoun, it often replaces a singular noun. As a determiner, it specifies a single entity. As a noun, it refers to the number 1.