To investigate thoroughly or probe into something; to get to the bottom of an issue or examine it closely.
問題の原因を突き詰める必要がある。
We need to get to the bottom of the problem's cause.
科学者たちはその現象を突き詰めて研究した。
The scientists probed the phenomenon thoroughly in their research.
契約書の条項を突き詰めて確認した。
I examined the contract clauses closely and confirmed them.
To be obsessed with or preoccupied by a thought; to brood over something — often implying excessive worry or fixation.
彼は細かい点にこだわり、いつも突き詰める傾向がある。
He tends to obsess over minor details and always pushes things to the extreme.
その一点が気になって夜も眠れず、突き詰めて考えてしまった。
That one point bothered me so much I couldn't sleep and kept brooding over it.
真実を突き詰めるあまり人間関係が悪化した。
In pursuing the truth too insistently, personal relationships deteriorated.