idiom · taking on a crucial responsibility single-handedly; acting as a pillar of strength who supports a whole situation or organization

在企业面临破产的危急关头，他一柱擎天，挽救了局势。

expression · reaching high into the sky as if to support the heavens like a single pillar; used to describe tall peaks, structures, or trees

那座孤峰一柱擎天，在云海中显得格外壮观。