noun
military transport vessel
A general term for ships used by the military to transport troops, equipment, or supplies.
輸送艦艇が物資を前線に運んだ。
The military transport vessel carried supplies to the front line.
輸送船 is a broader term for any transport ship, including civilian ones, while 輸送艦艇 specifically refers to military vessels.
Compound of 輸送 (transport) + 艦艇 (naval vessel).