unadaptable

unalterable

adamant adamantine determined dogged dyed-in-the-wool firm fixed hard hard-and-fast immovable immutable implacable indomitable inexorable intractable invariable iron ironclad obdurate obstinate relentless resolute rigid rigorous set set in one's ways single-minded stand one's ground staunch steadfast steely stiff strict stringent unbending unchangeable uncompliant uncompromising unrelenting unswayable unyielding

inductile inextensible inflexible rigid stable stiff unbending unyielding

elastic

adamant immutable intractable obstinate resolute rigid rigorous steadfast strict stringent uncompromising unyielding

adamantine determined dogged dyed-in-the-wool firm fixed hang-tough hard hard-and-fast immovable implacable indomitable inexorable iron obdurate relentless set set in one's ways single-minded stand one's ground staunch steely stiff unbending unchangeable uncompliant unrelenting unswayable

amenable cooperative easygoing flexible irresolute lenient pliant soft submissive tolerant willing yielding

bendable elastic pliable reasonable resilient