‘Defence’ vs. ‘Defense’: What’s the difference?

In your ongoing study of writing and grammar, one of the differences you may come across is differences in spelling, such as “defence” instead of “defense,” and vice versa. Learn the difference between these two spellings, whether they have different meanings, and when you should use one or the other.

Write with Confidence using Editor

Elevate your writing with real-time, intelligent assistance

Learn more

What does “defense”/”defence” mean?

“Defense” and “defence” are both pronounced the same way, and they both have the same meaning: To safeguard something from enemies or attackers. Whether this includes a fortress or a nation’s borders, a rhetorical argument or dissertation, or a sports team’s goal or end zone, both words hold the same concept of warding off a potential loss.

Where is “defence” used?

In most British Commonwealth countries, this word is spelled with a c instead of an s. These countries include the United Kingdom, Canada, Australia, and New Zealand, and former British colonies.

If you are writing to an audience in these countries, your readers will be familiar with the word “defence.” Otherwise, Americans will be familiar with “defense” instead, and in many Commonwealth countries, the word “defense” will be used as well.

Common differences in British vs. American English

The question of “defense” versus “defence” is just another example of how language has evolved. In 1755, writer and lexicographer Samuel Johnson and his assistants compiled over 40,000 years into A Dictionary of the English Language, one of the world’s first dictionaries. This process took them eight years. Fifty years later, Noah Webster introduced the first American English dictionary—and the resulting Webster’s Dictionary is one of the global standards for the English language.

In Webster’s publications, he popularized American English revisions of British English. Many of the following revisions include eliminating the letter u from certain words that end in -our, reversing the suffix -re to -er, establishing -ize as the standard over -ise, and removing extra letters from the ends of certain words. Examples of the newer American revisions to existing British words include:

• Labor vs. labour
• Honor vs. honour
• Color vs. colour
• Center vs. centre
• Theater vs. theatre
• Program vs. programme
• Apologize vs. apologise
• Paralyze vs. paralyse
• Check vs. cheque

Similarly, “defense” versus “defence” became one of Webster’s revisions.

How to change your operating system’s languages

In Microsoft 365 and Windows 11, there are Language Accessory Packs for British English and American English, which is the default setting. They are listed as English (United States) and English (United Kingdom).

This is why you may see the word “defence” appear as a spelling error when you’re writing. Because your system understands that you’re likely writing for an American audience, the spell-checker will highlight this word as a mistake with a red wavy line.

Here’s how you can change your Microsoft 365 language settings:

• Be sure that you have the correct Language Accessory Pack installed
• In any Microsoft 365 application, select File > More > Options.
• Select the Language option. In the Office authoring languages and proofing section, the default language will be displayed as English (United States).
• Select Add A Language…and scroll down to English. Here, you can add different versions of English from different English-speaking regions around the world, including the United Kingdom.

Alternatively, you can add “defence” and other British English spellings to your existing dictionary for spellcheck to recognize it as correct in the future. Select the word with your right mouse button, then select Add to dictionary in the Spelling menu.

The English language is full of subtle differences between words that can impact how your audience reads your work. Read about the differences between epigrams, epigraphs, and epilogues, when to use “that” or “who,” and the meanings of “principal” versus “principle.”