incursion
n. C1 Advanced US //ˌɪnˈkɝʒən// UK //ɪnkˈɜːʃən// in·cur·sion
n. a sudden attack or a small group of people entering a place where they are not welcome. It is often used to describe a military move into an enemy's territory.
n. a sudden, often violent, entry into a territory or area; a military attack or raid. Often implies a temporary or limited movement rather than a full-scale invasion.
The army launched a small incursion into the enemy's camp.
The border patrol reported a sudden incursion of illegal vehicles across the river during the night.
While the initial incursion was met with heavy resistance, the strategic placement of the troops allowed for a swift and decisive withdrawal before reinforcements arrived.
From Middle English, borrowed from Old French, from Latin incursiō.