Which of the following words is not a noun?

Explanation

Put simply, a noun is a word used to indicate a person, thing, place or idea. Examples of nouns are "a house", "a car", "a flower, "a girl", "a man", "a thought", "a smile". In some languages, nouns are assigned to genders, such as masculine, feminine and neuter (or other combinations). Nouns do not have gender in Modern English, however.