marines
n. C / Un. a group of soldiers who are trained to fight on land and at sea. They often travel on ships and are usually the first to arrive in a conflict.
n. a military force specifically trained for amphibious operations, serving as a specialized branch that bridges naval and land warfare. Often functions as a collective plural when referring to the organization.
He joined the marines right after finishing high school.
The marines were deployed to the coastal region to secure the harbor for incoming aid ships.
Historical accounts of the conflict emphasize the role of the marines in establishing a beachhead under heavy fire, which allowed the rest of the army to land safely.
When referring to the branch of service, it is often capitalized as 'the Marines'. As a plural noun, it refers to the individual members of that force.