[more obstinate; most obstinate]
1 : refusing to change your behavior or your ideas : STUBBORN
his obstinate refusal to obey
an obstinate little boy
her obstinate behavior
My parents remain as obstinate as ever.
2 : difficult to deal with, remove, etc. : STUBBORN
an obstinate stain
a very obstinate problem
— obstinacy /ˈɑːbstənəsi/ noun [noncount]
— obstinately adverb
people who cling obstinately to the past
He obstinately refused to obey.