having a frame or reinforcements strengthened or made rigid by brass, bronze, etc., as a trunk or chest.

rigid; inflexible

brassbound regulations.

impudent; brazen

brassbound presumption.

adjective

adamant , adamantine , die-hard , grim , implacable , incompliant , inexorable , inflexible , intransigent , iron , obdurate , relentless , remorseless , rigid , unbendable , unbending , uncompliant , uncompromising , unrelenting , unyielding