What does defence mean?
Defence is a noun describing the act of protecting someone or something from attack, harm, or criticism. It spans several related senses: physical protection, as in fortifications or military measures; legal advocacy, where it denotes the case presented on behalf of a defendant; sporting usage, where it names the players who stop the opposition scoring; and rhetorical justification, as when someone offers a defence of their actions or beliefs. Spelled with a 'c' in British, Canadian, and Australian English but with an 's' ('defense') in American English, it is one of the most visible markers of transatlantic orthographic difference. Derived from Latin through Old French, the word sits within a large family including 'defend', 'defensive', and 'defendant'. Common phrases such as 'in defence of', 'line of defence', and 'defence mechanism' show how deeply embedded it is across law, politics, psychology, and everyday speech.
The action of protecting someone or something from attack, harm, or injury; also the means used to provide such protection.
"The city's ancient walls were its first line of defence."
In British, Canadian, and Australian English this is the only accepted spelling; American English uses 'defense'.
The case presented by or on behalf of a defendant in a legal proceeding; the defendant's answer to the charges brought against them.
"The defence argued that the evidence had been obtained unlawfully."
In sport, the portion of a team responsible for preventing the opposition from scoring, or the tactics they employ.
"Their defence held firm under relentless pressure in the final minutes."
An argument or justification offered in support of a person, action, idea, or position.
"She delivered a passionate defence of press freedom at the conference."
The plural 'defences' is common when referring to multiple protective measures, fortifications, arguments, or defensive strategies. Note that American English spells it 'defenses'.
"The fortress's outer defences included a moat, a drawbridge, and two concentric walls."
Every time you write 'licence', 'offence', or 'defence' in British English, you're keeping alive a French-influenced spelling that America quietly dropped centuries ago.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of defence
The word 'defence' entered Middle English around the 14th century, borrowed from Old French 'defense' (later 'défense'), which itself derives from the Late Latin 'defensa', a noun use of the feminine past participle of 'defendere', meaning 'to ward off, protect'. The Latin verb combines 'de-' (away) with 'fendere' (to strike), giving the literal sense of striking away an attacker. The spelling with '-ce' reflects French influence and became fixed in British English, while American English later standardized on '-se'. Cognates and relatives include 'defend', 'defensive', 'defendant', and 'defensible', all tracing back to the same Latin root.
Related word forms
How defence is actually used
'Defence' is the standard spelling in British English, Canadian English, Australian English, and other varieties following British conventions, while 'defense' predominates in American English. The word carries no strong register constraints — it appears equally in formal legal, military, journalistic, and everyday contexts. In legal usage it refers both to the defendant's overall case and to specific legal justifications (such as self-defence or insanity).
Easily confused with defence
'Defence' is the British English spelling of the same word, while 'defense' is the standard American English spelling — they are pronounced identically and mean exactly the same thing.