unassailable
un-uh-SAY-luh-buladjMeaning too strong to be attacked or questioned
Memory hook un-a-SAIL-able: no ship can SAIL in. The pirates sail at the island fort again and again, but its walls never give way: the fort is unassailable.
With a twenty-point lead and two minutes left, the team’s position looked unassailable.
In context Her reputation for honesty was unassailable; in forty years of running the store, she had never once shortchanged a customer.
Similar impregnable, invulnerable, irrefutable, secure
Opposite vulnerable, weak, questionable
From un- (not) + assailable, from assail (to attack), from Latin ad- (at) + salire (to leap).