suru verb (special), intransitive verb
Obsolete term for military invasion or raiding. Not used in modern Japanese; replaced by words like 侵略する or 攻め込む.
古い文献では、敵国が寇する様子が記されている。
In old documents, the invasion by an enemy country is recorded.
The kanji 寇 means 'bandit' or 'invader'. The reading こう is the on'yomi. The exact historical derivation of the verb 寇する is uncertain, but it follows a classical pattern of forming suru verbs from single kanji.