Pair (noun)

1. A set of two similar things used together.
2. A couple regarded as a unit.
3. A pair of people or animals.
4. Two things of the same size and shape, especially matching socks.
5. A couple or partnership.

Origin:

Middle english: from old french paire, from latin paria "equals", from par "equal".

Examples:

1. She brought a pair of gloves.
2. The pair of shoes went well with her dress.
3. They make a great pair.
4. The couple is often referred to as a pair.
5. A pair of horses was needed to pull the wagon.