TOEIC Link Part 5: cannon versus canon
Cannon and canon are separated by a single n, but that letter marks a change of meaning from weaponry to established rules. Cannon (double n) is a large gun or artillery piece. Canon (single n) is a body of accepted standards, rules, or authoritative works. Part 5 rewards you for asking whether the blank names a weapon or a set of established principles. For the wider set of look-alike traps, start with the commonly confused word pairs master index.
The core rule: weapon versus body of rules
- cannon (noun) = a large mounted gun or piece of artillery; also used figuratively in phrases like loose cannon (an unpredictable person). The museum displays a bronze cannon from the 1700s. / An unreliable spokesperson can be a loose cannon for the brand. It answers what heavy weapon is meant? Anchor it with the double -nn-: a cannon is big, so it gets an extra n.
- canon (noun) = an accepted body of rules, standards, or works regarded as authoritative; also a general principle or criterion. The guideline reflects the established canon of accounting practice. / The report broke a basic canon of professional ethics. It answers what set of accepted standards is meant? Anchor it with the single n and the related word canonical (regarded as standard).
A quick anchor: cannon (double n) = a big gun; canon (single n) = a set of rules or standards. The bigger word is the bigger object; the leaner word is the set of principles.
Why Part 5 likes this pair
The two words differ by only one letter and sound similar, so the wrong option passes a quick glance. The item is decided by the surrounding meaning: military or figurative weaponry points to cannon, while rules, standards, or authoritative works point to canon.
Following the accepted __ of the profession, the auditor documented every assumption.
The sentence is about accepted professional standards, so it needs canon.
The exhibit's centerpiece is a restored naval __ from the last century.
The blank names a large naval weapon, so it needs cannon.
Spotting the clue
Check whether the blank is about firepower or about accepted standards:
- Is the sentence about a weapon, artillery, or a figurative "loose cannon"? → choose cannon (a mounted cannon, cannon fire, a loose cannon).
- Is the sentence about accepted rules, standards, principles, or authoritative works? → choose canon (the canon of practice, a canon of ethics, the literary canon).
A quick test: can you replace the word with "body of rules" or "accepted standard"? Then it is canon. Does it name a gun or an unpredictable person? Then it is cannon. In TOEIC business scenarios, canon appears in passages about professional standards, ethics, and best practice, while cannon shows up in descriptions of museums, history, or the idiom loose cannon for someone off-message. For more pairs where a single letter shifts the meaning, see the business and finance confusable pairs study guide. Another single-letter trap worth reviewing next is council versus counsel.