half watch ashore; port and starboard liberty
Naval term: shore leave granted to half of a ship's crew at a time, while the other half remains on duty. Used in military or maritime contexts.
Today was half watch ashore, and half of the crew was allowed to go ashore.
半舷上陸の時間は限られているので、みんな急いで準備をした。
Since the time for port and starboard liberty is limited, everyone hurried to get ready.