Fidei defensor
“Defender of the Faith.”
Royal title of British monarchs
What does “Fidei defensor” mean?
Fidei defensor translates as “Defender of the Faith.”
A title of the British monarch, abbreviated F.D. or Fid. Def. on coins.
“Fidei defensor” word by word
| Latin | English | Grammar |
|---|---|---|
| Fidei | of the faith | genitive singular of fides, “faith”; the genitive here means “of” the faith |
| defensor | defender | nominative singular of defensor, “defender”, from defendo, “I defend”; a masculine agent noun |
How to pronounce “Fidei defensor”
The difference is small. Classical sounds the e in fidei as a long “ay” and the final -ei as a diphthong; Church Latin says it as “eh”. In both, stress the first syllable of fidei and the second of defensor.
The story behind it
Word for word the title says “defender of the faith”. It is a royal title, not a saying, and it belongs to the British monarch.
Pope Leo X gave it to Henry VIII in 1521, after Henry wrote a book against Martin Luther’s teachings. After Henry broke with Rome, the pope withdrew the title.
In 1544 Parliament granted it to the Crown, and English and British monarchs have used it ever since, even though the faith now defended is the Church of England, not the Roman one.
The title still appears on British coins as F.D. or Fid. Def., short for Fidei Defensor.
How to use “Fidei defensor”
It suits a caption about a ruler or a historical subject, a quiz or essay on British monarchy, or a motto for someone who sees themselves as a protector of their beliefs. On coins and in heraldry it is a recognisable royal label.
- Latin
- Fidei defensor
- English
- Defender of the Faith.
- Source
- Royal title of British monarchs
- Era
- Renaissance
- Theme
- Faith
Common mistakes
- It is a title, not a proverb. It names the monarch’s role and is not a general motto about faith.
- Fidei is genitive, “of the faith”. Writing fides defensor is wrong, because fides is the nominative.
- For a female monarch the Latin is Fidei Defensatrix, with the feminine ending, though on coins the abbreviation F.D. is the same.
- The title was not granted for the Church of England. It was first given by the pope for defending Roman Catholic teaching.
Questions about “Fidei defensor”
What does “Fidei defensor” mean literally?
“Defender of the faith”. Fidei is “of the faith” and defensor is “defender”.
Who first held the title “Fidei defensor”?
Henry VIII received it from Pope Leo X in 1521. The pope later withdrew it, and Parliament granted it to the Crown in 1544.
How do you pronounce “Fidei defensor”?
Classically it is FEE-day-ee day-FEN-sor; in Church Latin it is FEE-deh-ee deh-FEN-sor. The stress falls on the first syllable of fidei and the second of defensor.
What do F.D. and Fid. Def. on coins stand for?
Both abbreviate Fidei Defensor, “Defender of the Faith”, a title of the British monarch used on coins.
More to explore
Translation and grammar checked by Latin Quoter · last reviewed November 2026
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