unflexible

arthritic creaky rigid solid stark tense thick tight wooden

brittle buckram firm refractory rheumatic set

annealed benumbed cemented chilled congealed contracted fixed frozen graceless hardened immalleable impliable incompliant indurate inelastic jelled mechanical numbed ossified petrified resistant solidified starched starchy steely stiff as a board stony taut thickened unbending ungraceful unsupple unyielding

bending flexible loose pliable slack soft

indefinite supple

pliant

crisp firm obstinate reserved

aloof distant do-or-die dug in formal hard as nails hard-line hold one's ground hold the fort hold the line incompliant inelastic inexorable inflexible intractable locked-in obdurate relentless resolute set in stone severe single-minded standing one's ground standing pat sticking to one's guns stiff strict stubborn uncompromising unrelenting unswayable unyielding uptight

flexible soft yielding

bending pliable pliant relaxed