invaders
n. countable B2 Upper Intermediate US //ˌɪnˈveɪdɝz// UK //ɪnvˈeɪdəz// in·vaders
n. people or groups who enter a country or place by force to take control of it.
n. individuals or groups that enter a territory by force with the intent of conquest or occupation.
The city walls were built to keep out invaders.
The local population retreated into the mountains to hide from the foreign invaders who had crossed the border.
Historians often debate whether the collapse of the empire was caused by internal decay or the relentless pressure from external invaders seeking new lands.
Usage
Usually appears in the plural form when referring to an army or a collective force.