离群索居

离群索居 [lí qún suǒ jū]

1. ■ keep oneself to oneself; cut oneself off from society; forsake society and live alone; hole up; hold aloof; isolate oneself; leave society and live alone; leave the crowd and live alone; live alone, cut off from society; live in solitude; live out of the world; live the life of a recluse; live within oneself; plough a lonely furrow; retire [withdraw; shut oneself] into one's shell:

那个自信的家伙总是离群索居。 That confident fellow always keeps himself to himself.