四sì面miàn楚chǔ歌gē

Literal: on all four sides, songs of Chu
Figurative: To be besieged on all sides and utterly isolated; surrounded by enemies with no way out and no allies.

Where does 四面楚歌 come from?

Near the end of the Chu-Han contention, King Xiang Yu of Chu was surrounded at Gaixia by Liu Bang's Han forces. At night the Han army had songs of Chu sung from all four sides of the camp. Hearing them, Xiang Yu believed the Han had already conquered all of Chu and that even his own people had surrendered; he realized all was lost.

Source (出处): 《史记》

How is 四面楚歌 used? Two examples

公gōng司sī决jué策cè接jiē连lián失shī误wù，如rú今jīn资zī金jīn链liàn断duàn裂liè、客kè户hù流liú失shī，管guǎn理lǐ层céng已yǐ是shì四sì面miàn楚chǔ歌gē。
With one bad decision after another, now that funding has dried up and clients are leaving, management is cornered on every side.
他tā在zài会huì上shàng得dé罪zuì了le所suǒ有yǒu同tóng事shì，提tí案àn时shí四sì面miàn楚chǔ歌gē，没méi有yǒu一yī个gè人rén愿yuàn意yì支zhī持chí。
He had offended every colleague in the meeting, so when he put forward his proposal he found himself completely isolated, with not a single person willing to back him.

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