Can Double Be a Noun?

double (noun) double (adverb) double–barreled (adjective)

What type of word is double?

The word double can function as an adjective (e.g. a double murder, a double portion), a verb (e.g. 'The population of the city has doubled over the past twenty years'), a determiner (e.g. 'He now earns double the amount he used to' or 'It'll cost you double what you paid last year') and a noun.

Is there such a word as double?

composed of two like parts or members; twofold in form; paired: double doors; a double sink. of, relating to, or suitable for two persons: a double room. twofold in character, meaning, or conduct; dual or ambiguous: a double interpretation.