里应外合

裡應外合

lǐyìng-wàihé

idiom

Meanings

1 to coordinate outside and inside attacks
2 insiders and outsiders acting in concert (often to pull off a scheme)

Characters

to respond; echo

to join; combine

Examples

敌军里应外合，攻破了城池。

Díjūn lǐyìngwàihé, gōngpò le chéngchí.

The enemy coordinated inside and outside forces and breached the city.

这次盗窃明显是里应外合。

Zhècì dàoqiè míngxiǎn shì lǐyìngwàihé.

This theft was clearly an inside job with outside help.

销售和市场部里应外合，才能把产品推出去。

Xiāoshòu hé shìchǎngbù lǐyìngwàihé, cáinéng bǎ chǎnpǐn tuīchū qù.

Sales and marketing have to work hand in glove to get the product out there.

Tips

history

From Yang Zi's (杨梓) Yuan drama 《豫让吞炭》: Zhao, Han, and Wei 'plotted together, coordinating inside and outside' — 里应外合 — to flood and rout the army. Originally a military tactics phrase.

usage

Usually about schemes: insiders open the gate while outsiders attack, or a staff member tips off thieves. Can also be used neutrally for legitimate team coordination (field team + HQ). 里应 = insider responds; 外合 = outsider combines forces.

Stroke Order

里 lǐ

应 yīng

外 wài

合 hé