OB'DURATE, adjective [Latin obduro, to harden; ob and duro.] 1. Hardened in heart; inflexibly hard; persisting obstinately in sin or impenitence. 2. Hardened against good or favor; stubborn; unyielding; inflexible. The custom of evil makes the heart obdurate against whatsoever instructions to the contrary. 3. Harsh; rugged; as an obdurate consonant. [Little used.] OB'DURATE, verb transitive To harden. [Not used.]
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI