/ ˈkəʊstgɑːd; NAmE ˈkoʊstgɑːrd/ noun
1.
(usually the coastguard ) [ sing. ] an official organization (in the US a branch of the armed forces) whose job is to watch the sea near a coast in order to help ships and people in trouble, and to stop people from breaking the law :
The coastguard was alerted.
They radioed Dover Coastguard.
a coastguard station
2.
[ C ] ( especially BrE ) ( US usually coast·guard·man ) a member of this organization