The Meaning of Semper Fi: What It Is and How To Use It

Do you know the definition of the phrase semper fi? This guide will provide you with all of the info you need on the phrase semper fi, including its definition, etymology, example sentences, and more!

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What does the phrase semper fi mean?

According to Marines, the term semper fi is a Latin phrase that is short for “semper fidelis.” This phrase means “always faithful.” Semper fi is the motto of every member of the U.S. Marine Corps. The United States Marine Corps uses the phrase to reflect a collective and eternal commitments to succeeding in battles, the [progress of the nation of the United States, and a loyalty to the Marine Corps at large. This phrase develops a bond between Marines and shows that being in the Marine Corps is not just a job, but a warriorhood. This phrase united individual marines and military units with their fellow Marines also performing military service, or who have served in the past. 

In the Marine Corps, the phrase semper fi is used as a greeting, motivation, and generally used expression to unite past and present members of the Marine Corps. The phrase represents tradition and responsibility. An exchange between two Marines might go as follows:

Marine 1: Semper Fi!

Marine 2: Semper Fi!

Marine 1: Semper Fi!

Marine 2: Oorah!

This phrase is also the title of the official march of the Marine Corps which was composed by John Philip Sousa in 1889. According to Constitution, modern lyrics to the song were added in 2009. A selection of these lyrics is below:

Don’t you know the Marines are marching,

When you can hear this song?

So, when all of the boys are marching,

Sing as they march along.

Yes, we know the Marines are coming!

Everyone sing along!

As we hear how the drums are thrumming,

Welcome the marching throng!

You can see as they pass before us,

Shoulders square, heads held high;

That the pride of the Corps is glorious,

Hail to our “Semper Fi!”

Using the phrase semper fi is an identifier that one was in the Marines or is currently in the Marines. This phrase can also be used by families of Marines so long as they explain that they are simply the relative of a Marine. Some people will also respond to the term semper fi with the Marine chant “oorah” which is different from the Army, Navy and Coast Guard chants. This battle cry was popularized in the 20th century and is used as a verbal indication of enthusiasm.

What is the origin of the phrase semper fi?

The phrase semper fi was first used as the official motto of the U.S. Marine Corps in 1883. According to Our Military, this phrase was adopted by Colonel Charles McCawley. However, this phrase was not always the official motto of the Marines. According to ABC 7 Chicago, there were three official mottos that the Marines would use before semper fidelis was adopted. These were, “By Sea and By Land,” “Fortitudine,” and “To the shores of Tripoli.” This phrase comes directly from Latin. The phrase semper fidelis in Latin means always faithful. 

How can the phrase semper fi be used in a sentence?

The phrase semper fi is exclusively used when two members or former members of the U.S. Marine Corps are speaking to each other. The phrase can be used as a greeting or expression of encouragement, and is often used as an exclamation. It is inappropriate for someone who is outside of the Marine Corps to use this expression. 

What are synonyms and antonyms for the phrase semper fi?

There are many different words that mean faithful that one can use in place of the term semper fi. The terms semper fi and semper fidelis are very closely associated with the United States Marine Corps, so one should opt to use a synonym if they are not associated with this branch of the military. You wouldn’t want someone thinking you are a commandant of the Marine Corps! Synonyms are also useful to know if you want to expand your vocabulary or to avoid repeating yourself. This list of synonyms for the word faithful is provided by Thesaurus

  • enduring
  • sincere
  • genuine
  • unchanging
  • scrupulous
  • loving
  • resolute
  • circumspect
  • behind one
  • devoted
  • veracious
  • trusty
  • allegiant
  • tried
  • steady
  • firm
  • honorable
  • loyal
  • obedient
  • dyed-in-the-wool
  • attached
  • affectionate
  • string along with
  • incorruptible
  • unwavering
  • honest
  • steadfast
  • constant
  • truthful
  • on the level
  • staunch
  • straight
  • dependable
  • fast
  • upright
  • tried and true
  • sure
  • true-blue
  • hard-core
  • unswerving
  • patriotic
  • reliable
  • confiding
  • true
  • dutiful
  • conscientious
  • ardent
  • trustworthy

There are also many different words that mean the opposite of faithful. These are called antonyms. Antonyms are very useful to know to expand one’s vocabulary and better grasp the intricacies of the English language. This list of antonyms for the word faithful is also from Thesaurus

  • perfidious
  • fickle
  • unfaithful
  • deceitful
  • philandering
  • adulterous
  • adulterine
  • treacherous
  • cheating
  • not true to
  • wicked
  • traitorous
  • two-faced
  • two-timing
  • false-hearted
  • faithless
  • double-crossing
  • disloyal
  • of bad faith
  • untrue
  • sneaking
  • false
  • snaky
  • inconstant
  • untrustworthy
  • incontinent
  • treasonable
  • moonlighting
  • recreant
  • unreliable
  • shifty
  • unchaste
  • foresworn

Overall, the phrase semper fi is the motto of the United States Marine Corps. The USMC armed forces use this Latin phrase meaning always faithful to pledge their loyalty to the United States Marine Corps. The motto semper fidelis is also used as the title of the Marines’ Hymn, which is also known as the march of the Marines. This phrase is directly taken from Latin.