The Oxford Thesaurus An A-Z Dictionary of Synonyms - immovable adj.

1) unmovable, fixed, fast, rooted, set, immobile, stationary, motionless, stable, riveted, anchored, frozen: What happens when an irresistible force meets an immovable object? 2 immutable, unchangeable, unalterable, settled, set, unmovable, fixed, inflexible; unshakeable or unshakable, unswerving, firm, determined, steadfast, staunch, rigid, dogged, obdurate, unyielding, unwavering, resolute, unflinching, adamant(ine) , stony, impassive, unbending, impassive, emotionless, unmoved: Christmas day, which always falls on December 25th, is an immovable feast. Despite pleas for mercy, the judge was immovable and she was hanged the next day.