The act of invading; the act of an army that invades for conquest or plunder WordNet 3.0 & Open English WordNet

An invasion is a military offensive of combatants of one geopolitical entity, usually in large numbers, entering territory controlled by another similar entity, generally with the objective of either: conquering; liberating or re-establishing control or authority over a territory; forcing the partition of a country; altering the established government or gaining concessions from said government; or a combination thereof. Wikipedia

Military action of soldiers entering a foreign land. Wikipedia Disambiguation

Type of military offensive where armed forces of one polity forcibly enter another Wikidata

A military action consisting of armed forces of one geopolitical entity entering territory controlled by another such entity. OmegaWiki

A military action consisting of armed forces of one geopolitical entity entering territory controlled by another such entity, generally with the objective of conquering territory or altering the established government. Wiktionary

Military action. Wiktionary (translation)