Yes, it is a noun. It can mean a water flask or a snack bar.
The collective nouns are canteen of water and a canteen of cutlery.
In most cases, common noun.
Canteen can mean a couple of things. Canteen can mean the container you carry while camping, generally full of water. In military parlance, canteen also means the place where you go to eat. For further information and definition, here's a link to the dictionary.com definition. http://dictionary.reference.com/browse/Canteen
The plural form of the noun canteen is canteens.The plural possessive form is canteens'.
The collective noun for cutlery is 'a set of cutlery'.
Confederate States, if the canteen is from the US Civil War. If you are asking about a foriegn non-US canteen or modern canteen, I have no idea.
A flask is similar to a canteen.
Student Canteen was created in 1958.
Student Canteen ended in 1990.
Victory Canteen was created in 1971.
Hollywood Canteen was created in 1944.
Canteen Boy was created in 1993.