Antonyms of adj under_attack

1 sense of under attack

Sense 1
under attack (predicate), under fire (predicate) -- (subjected to enemy attack or censure; "an official under fire for mismanagement")

INDIRECT (VIA vulnerable) -> invulnerable -- (immune to attack; impregnable; "gunners raked the beach from invulnerable positions on the cliffs")

Similarity of adj under_attack

1 sense of under attack

Sense 1
under attack (predicate), under fire (predicate) -- (subjected to enemy attack or censure; "an official under fire for mismanagement")
       => vulnerable (vs. invulnerable) -- (susceptible to attack; "a vulnerable bridge")