This is the 11634th most frequent Swedish word.
orubblig
Unshakable; unwavering; steadfast.
Here 'orubblig' is used as an adjective to describe 'tro' (belief), meaning steadfast or unwavering.
Han hade en orubblig tro på sin förmåga.
He had an unwavering belief in his ability.
In this context, 'orubbliga' describes 'vilja' (will), emphasizing determination and firmness.
Hennes orubbliga vilja gjorde att hon aldrig gav upp.
Her unyielding will meant she never gave up.
Here, 'orubblig' modifies 'regel' (rule), indicating its inflexibility and constancy.