CANON/CANNON |
“Canon” used to be such a rare word that there was no temptation to confuse it with “cannon”: a large piece of artillery. The debate over the literary canon (a list of officially-approved works) and the popularity of Pachelbel’s Canon (an imitative musical form related to the common “round”) have changed all that—confusion is rampant. Just remember that the big gun is a “cannon.” All the rest are “canons.” Note that there are metaphorical uses of “cannon” for objects shaped like large guns, such as a horse’s “cannon bone.”