Make Your Editor Cry: Canon vs. Cannon

Canon with a single “-n” in the middle of the word is a noun. The singular form of canon is canon. The plural form of canon is also canon. The word canons is not a thing. Or a word. Canon most commonly refers to an accepted principle or a little rule or an authoritative list of books or texts. It can also refer to a particular member of the clergy or style of musical composition.

Cannon with a double “-nn” in the middle of the word is also a noun that refers to a large gun that is usually mounted on wheels. Until relatively recently in history, the cannon was a common military weapon. Think of the guns on the lower decks of an old pirate ship or think of the kind of field artillery pieces employed during the American War Between the States. The singular form of cannon is cannon. The proper plural form of cannon is also cannon. The word cannons is not a thing, or a proper word, despite the fact that Webster allows for it. (Remember, Webster is the repository of words in common usage, not necessarily proper usage.)

Examples:

Correct:

In the Stars Wars universe, there is some debate about whether the Disney spin-offs are really part of the Star Wars canon.
Each day at 5 p.m. on Fort Knox, a cannon is fired while the US flag is taken down.
It’s accepted as canon that more than one cannon is still referred to as cannon, not cannons.

Incorrect:

In the Stars Wars universe, there is some debate about whether books and comics are part of the Star Wars cannon.
Each day at 5 PM on Fort Knox, a canon is fired while the flag is taken down.
It’s accepted as cannon that more than one canon is still referred to as canon not canons.

The difference between canon and cannon really does come down to whether the word has “-n” or “-nn” in the middle. Both are nouns; both are pronounced identically; and both eschew using an “-s” at the end of the word for their plural forms. But obviously, they do not mean anything like the same thing.