adj. 25B6; adjective STUBBORN, obstinate, intransigent, inflexible, unyielding, unbending, pig-headed, mulish, stiff-necked; headstrong, unshakeable, intractable, unpersuadable, immovable, inexorable, uncompromising, iron-willed, adamant, firm, determined; Brit. informal bloody-minded.
malleable.