unfailing (adjective) unfailing: certain, unchanging
Sinonime: absolute,
assiduous, bottomless,
boundless, ceaseless, come-through,
consistent,
constant,
continual,
continuing,
continuous, counted on, delivering,
dependable,
diligent, dyed-in-the-wool,
endless,
eternal,
faithful, inexhaustible,
infallible, invariable,
loyal, never-failing,
persistent,
reliable, rock solid,
same,
solid,
staunch,
steadfast,
straight,
sure, surefire, there, tried-and-true,
true,
trustworthy, unflagging,
unlimited,
unrelentingAntonime: failing, impermanent,
uncertain,
unsure