One

A numerical value equal to 1; the first number in the set of natural numbers (especially in number theory); the cardinality of the smallest nonempty set. Ordinal: first.

The ordinality of an element which has no predecessor, usually called first or number one.

The neutral element with respect to multiplication in a ring.

The digit or figure 1.

A one-dollar bill.

One run scored by hitting the ball and running between the wickets; a single.

Used instead of ! to amplify an exclamation, imitating n00bs who forget to press the shift key while typing exclamation points.

A particularly special or compatible person or thing.

One thing (among a group of others); one member of a group.

The first mentioned of two things or people, as opposed to the other.

Any person (applying to people in general).

Any person, entity or thing.

Of a period of time, being particular; as, one morning, one year.

Being a single, unspecified thing; a; any.

Sole, only.

Whole, entire.

In agreement.

The same.

Being a preeminent example.

Being an unknown person with the specified name.

To cause to become one; to gather into a single whole; to unite.