rigid

adj.

[1]	stiff , stiff , unbending , unbendable , firm , hard , strong
[2]	inflexible , strict , inelastic , unyielding , undeviating , unalterable , set , firm , hard , adamant , hard-line , unbending , adamantine , steely , iron , strong , uncompromising , rigorous , unrelenting , intransigent , stringent , severe , strict , rigorous , stern , harsh , austere
[3]	rigorous , inflexible , unbending , exact , precise , unwavering , unqualified , unswerving , undeviating , demanding , strict , hard and fast , literal , nice , close , thorough , scrupulous , careful , conscientious , painstaking , meticulous , punctilious , exacting , strait-laced
[4]	obstinate , stubborn , pigheaded , inflexible , immovable , adamant , adamantine , fixed , set , obdurate , wilful , headstrong , dogged , persevering , determined , resolute , steadfast , resolved , tenacious , relentless , unrelenting , uncompromising , unadaptable , mulish , close-minded
[5]	fixed , set