Semper fidelis
“Always faithful.”
Latin motto; US Marine Corps motto since 1883
What does “Semper fidelis” mean?
Semper fidelis translates as “Always faithful.”
Loyalty that does not depend on circumstances. It is a promise to stand by people, values and duties, in good times and bad.
“Semper fidelis” word by word
| Latin | English | Grammar |
|---|---|---|
| Semper | always | an adverb; it does not change its form |
| fidelis | faithful, loyal | nominative singular, masculine or feminine, of the adjective fidelis (from fides, “faith, trust”); it agrees with an unstated subject, “(he/she/I/we are) faithful” |
How to pronounce “Semper fidelis”
The stress falls on the first syllable of semper and the second of fidelis in both systems. Classical has a short i in fidelis and a long ay sound; Church Latin has a long ee and a clipped eh.
The story behind it
Word for word the phrase says “always faithful”. It has no verb: Latin lets the adjective stand alone, so the sense is “(be) always faithful” or “(we are) always faithful”.
The phrase is not from a classical author. It is a motto of the later European tradition and was used for centuries by towns, noble families and institutions that wanted to advertise loyalty.
Since 1883 it has been the motto of the United States Marine Corps, usually shortened to “Semper Fi”. Most people today meet the phrase through that use.
How to use “Semper fidelis”
Fits a gift or card for a partner, close friend or family member, a motto for a team or a unit, and tattoos or engravings about loyalty. It also suits a caption on a photo of a veteran or a dog.
- Latin
- Semper fidelis
- English
- Always faithful.
- Source
- Latin motto; US Marine Corps motto since 1883
- Era
- Modern
- Theme
- Loyalty
Common mistakes
- The ending fidelis is the same for masculine and feminine, so a woman does not need to change it. Only the neuter plural would differ (fidelia).
- If you are speaking of several people, the plural is fideles (“semper fideles”), which is correct but less common.
- Do not spell it “Semper Fidelas” or “Semper Fidelius”; neither is Latin.
- Not to be confused with “Semper fortis” (“always brave”) or “Semper paratus” (“always ready”), which are different mottos.
Questions about “Semper fidelis”
What does “Semper fidelis” mean literally?
“Always faithful”. Semper is “always” and fidelis is “faithful, loyal”, related to fides, “faith, trust”.
Who said “Semper fidelis”?
No single author. It is a traditional motto used by towns and families long before the US Marine Corps adopted it in 1883.
How do you pronounce “Semper fidelis”?
In Classical Latin, SEM-per fih-DAY-lis. In Church Latin, SEM-per fee-DEH-lees. The stress is on the same syllables in both.
Is “Semper fidelis” correct Latin for a tattoo?
Yes. It is correct as it stands and works for any gender. Use “semper fideles” only if you mean several people.
More to explore
Translation and grammar checked by Latin Quoter · last reviewed November 2026
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