the prize to be won; the aim of a campaign
Historical idiom from Chinese history, referring to the throne or supreme power as the object of contention. Used metaphorically for any grand prize or goal in a struggle.
戦国時代、多くの武将が中原の鹿を追った。
During the Warring States period, many warlords chased the prize of supreme power.
彼は政界で中原の鹿を狙っている。
He is aiming for the top prize in the political world.
From the Classical Chinese saying 秦失其鹿、天下共逐之, recorded in the 『史記』. The lost “deer” symbolizes imperial rule, for which contenders struggle.