Specific rank in the Japan Maritime Self-Defense Force, equivalent to Vice Admiral in other navies. Not a general term for vice admiral.
彼は海将に昇進した。
He was promoted to Vice Admiral (JMSDF).
海将が艦隊を指揮
The Vice Admiral commands the fleet.
rear admiral (JMSDF)
Compound of 海 (sea, maritime) and 将 (general, commander). The reading is on'yomi. The term was created for the Japan Maritime Self-Defense Force rank system.