She was so obdurate that no amount of persuasion could make her even try to learn the piano.
"Industries are often reluctant to modernize, and obdurate about their right to use natural resources.""The most obdurate foes of the Clean Water Act were the fertilizer companies."
I try to explain my ideas and feelings to my brother, but there is no use, for he is very obdurate to change
Although he was recently released from prison, the convict still had the obdurate conscience of an old sinner.
Ebenezer Scrooge was an adamant obdurate, until the ghost's of Christmas past, present & future showed him the error of his way's.