an amphibious division of the United States Navy
"The marines landed on the beach to secure the island for the rest of the fleet."
members of a body of troops trained to serve on land or at sea
"The marines landed on the beach and quickly secured the shoreline against enemy forces."
plural of marine
"The spelling variation shows that both forms are acceptable when referring to military personnel trained in amphibious warfare."
Alternative form of marine corps
Alternative form of marines
In plain English: Marines are soldiers who specialize in fighting on land, sea, and air as part of an army's naval force.
"The marines landed on the beach to secure the island during the battle."
The United States Marine Corps.
"The marines landed on the beach to secure the perimeter before the main army arrived."