external threat; foreign menace
Refers to threats or pressure from outside a country, often used in political or historical contexts. Commonly appears in the set phrase 内憂外患 (ないゆうがいかん, 'troubles at home and abroad').
Japan at that time was troubled by external threats.
In an era of troubles both at home and abroad, the nation was forced to make major decisions.
treason; conspiracy against one's country
troubles both at home and abroad
Compound of 外 (outside, external) and 患 (trouble, affliction). The exact historical derivation is uncertain, but the term has been used in classical Chinese-influenced Japanese to denote foreign threats.