Definitions:

1. Denotes a hardened attitude, especially in matters where flexibility or empathy might be expected, often implying a refusal to soften one's stance or opinion. NOUN
   • Her obduracy in refusing to apologize strained relationships within the family.
2. Refers to the quality of being stubbornly resistant to change, persuasion, or emotional influence. NOUN
   • His obduracy in refusing to apologize only deepened the conflict, despite repeated attempts at reconciliation.

Synonyms:

• adamance
• harheadedness
• intransigence
• perinacity
• persistence
• self-will
• stubborness