Historically, marines serve as a navy's ground troops. In fact, the word "marine" is the French word for sea, which may be why the French military historically called English troops - who all had to arrive by sea - "marines."What is the Marine Corps saying?
Short for "Semper Fidelis," the U.S. Marine Corps motto translates from Latin as "Always Faithful.". The term is used both in direct reference to the official motto and as a colloquialism among Marines. In a video on the subject from the Marine Corps website, one Marine says, "There's no such thing as an ex-Marine, no such thing as a former Marine.What does Semper Fi mean in the Marines?
Semper Fi is short hand for Semper Fidelis, the Marine Corps motto. Translated into English from Latin, it means “Always Faithful.” Marines use it orally, as well as in written form. It’s both a greeting and a leave taking.