1. (a.) Firmly fixed or established; fast fixed; firm.

2. (a.) Not fickle or wavering; constant; firm; resolute; unswerving; steady.

abiding accordant adamant age-long aged alike ancient antique ardent assiduous automatic balanced calculable changeless chronic committed consistent consonant constant continuing continuous cool correspondent dedicated deep-rooted dependable determined devoted diligent diuturnal dogged durable enduring equable equal even evergreen faithful faithworthy fast fiducial firm firm as Gibraltar fixed flat flinty frozen hardy homogeneous immobile immotile immotive immovable immutable imperturbable in equilibrium inalterable indefatigable indomitable industrious inexorable inflexible insistent intact intransient invariable inveterate invincible inviolate irremovable lasting level liege long-lasting long-lived long-standing long-term longeval longevous loyal macrobiotic marble-constant measured mechanical methodic monolithic never-failing never-tiring obdurate obstinate of a piece of long duration of long standing ordered orderly patient patient as Job perdurable perduring perennial permanent perpetual perseverant persevering persistent persisting pertinacious plodding plugging predictable preoccupied quiescent rapt regular relentless reliable remaining resolute resolved rigid robotlike secure sedulous sempervirent set settled single-minded sleepless slogging smooth solid sot sound stable static stationary staunch staying steady steely stubborn substantial sure surefire sustained systematic tenacious tested tireless torpid tough tried tried and true TRUE true-blue trustworthy trusty unabating unaltered unbending unbroken unchangeable unchanged unchanging unchecked unconquerable undaunted undeflectable undestroyed undeviating undifferentiated undiscouraged undiversified undrooping unfading unfailing unfaltering unflagging unflappable unflinching uniform unintermitting uninterrupted unmovable unnodding unqualified unquestioning unrelaxing unrelenting unremitting unruffled unshakable unshaken unshifting unsleeping unswerving untiring unvaried unvarying unwavering unwearied unwearying unwinking unyielding utterly attentive vital weariless well-balanced well-founded well-grounded wholehearted without nerves