Final answer:
The United States Marine Corps' motto is 'Semper Fidelis,' which translates to 'Always Faithful' in English, signifying the Marines' enduring loyalty and commitment.
Step-by-step explanation:
The Motto of the United States Marine Corps
The motto of the United States Marine Corps is 'Semper Fidelis' which translates from Latin to English as 'Always Faithful'.
This motto signifies the lifelong loyalty that Marines have to the Corps and to their country, representing an unyielding commitment to their duties and to each other.
This ethos has been captured in iconic imagery and historical milestones, such as the Marines raising the American flag on Iwo Jima during World War II, which demonstrates the valor and fidelity embodied by the motto 'Semper Fidelis'.