Firm and unshakable; having a resolute, steadfast attitude or position.
社長は確固不抜の決意で改革を押し進めた。
The president pushed forward the reforms with an unshakable resolve.
彼女は信念に基づき、確固不抜に行動した。
She acted firmly and unperturbed, based on her convictions.
その党の方針は確固不抜で、多くの支持を集めた。
The party's policy was steadfast and gathered much support.