Nouns

(n)atrophy, witheringany weakening or degeneration (especially through lack of use)

Adjectives

(s)annihilative, annihilating, devastating, witheringwreaking or capable of wreaking complete destruction“possessing annihilative power”, “a devastating hurricane”, “the guns opened a withering fire”
(s)annihilating, devastating, witheringmaking light of“afire with annihilating invective”, “a devastating portrait of human folly”, “to compliments inflated I've a withering reply” (W.S.Gilbert)