noun
landing operations; amphibious assault
Military term for an operation where forces land on a hostile shore, typically involving naval and ground elements.
連合軍はノルマンディー上陸作戦を決行した。
The Allied forces carried out the Normandy landing operations.
上陸 means 'landing' or 'disembarkation' in general, while 上陸作戦 specifically refers to a military landing operation.
Compound of 上陸 (じょうりく, 'landing') + 作戦 (さくせん, 'operation').