Synonyms for Devastating (same or very similar meaning)
WordNet sense 1 (making light of):
withering, annihilating
WordNet sense 2 (exhibiting lack of respect; rude and discourteous):
disrespectful
WordNet sense 3 (physically or spiritually devastating; often used in combination):
crushing
WordNet sense 4 (wreaking or capable of wreaking complete destruction):
annihilative
WordNet sense 5 (causing destruction or much damage):
destructive
From the ODE community, based on WordNet
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