yù dí
armed enemy of the nation
enemy of the Emperor
fig. championship challenger
contender opposing champion in sporting contest
fáng yù gōng shì
fortification
defensive structure
wài yù qí wǔ
internal disunity dissolves at the threat of an invasion from outside (idiom)
xiōng dì xì yú qiáng , wài yù qí wǔ
internal disunity dissolves at the threat of an invasion from outside (idiom)
fáng yù lǜ
earned run average (baseball)