1
cannot allow (oneself) to live (with someone) under the canopy of heaven;cannot allow (the sworn enemy) to live in this world;irreconcilable (enemy)
不倶戴天の敵と言われるほど、どうしてそんなに嫌われたかなあ。
He said I was his archenemy. How did we arrive at a situation like this?
Other forms
不俱戴天 【ふぐたいてん】 (search-only kanji form)