iron purpose; firm resolve
A rare, literary noun meaning unwavering determination. Not used in everyday conversation; more likely encountered in formal writing, speeches, or as a personal name.
彼は堅志をもって難局に立ち向かった。
He faced the difficult situation with iron resolve.
Compound of 堅 (firm, hard) and 志 (will, purpose). The exact historical derivation is uncertain; it is a Sino-Japanese word (kango) likely coined in literary or formal contexts.