pigheaded (adj.)

• balking
• balky
• bigoted
• bullheaded
• case-hardened
• dogged
• dogmatic
• fanatic
• hardheaded
• headstrong
• intolerant
• intractable
• mulish
• obstinate
• opinionated
• overzealous
• persevering
• pertinacious
• perverse
• restive
• self-willed
• set
• stiff-necked
• strong-willed
• stubborn
• sulky
• sullen
• tenacious
• uncooperative
• unregenerate
• unyielding
• willful