one

/wʌn/ pronoun

Definition

PARTICULAR PERSON/THING › used to refer to a particular person or thing in a group that has already been talked about: I've just made some scones, do you want one? Throw those gloves away and get some new ones. Chris is the one with glasses.

GENERAL formal › any person in general: One ought to respect one's parents.

one at a time › separately: Eat them one at a time.

one by one › separately, with one thing happening after another: One by one the old buildings have been demolished.

one another › each other: How can they reach an agreement if they won't talk to one another?

(all) in one › combined into a single thing: It's a vacation and art course all in one.

(Definition of one pronoun from the Cambridge Learner's Dictionary © Cambridge University Press)