Adjective frightful has 3 senses
- atrocious, frightful, horrifying, horrible, ugly - provoking horror; "an atrocious automobile accident"; "a frightful crime of decapitation"; "an alarming, even horrifying, picture"; "war is beyond all words horrible"- Winston Churchill; "an ugly wound"
Antonym: unalarming (indirect, via alarming)
- frightful - extreme in degree; "in a frightful hurry"; "spent a frightful amount of money"
Antonym: ordinary (indirect, via extraordinary)
- fearful, frightful, terrible - extremely distressing; "fearful slum conditions"; "a frightful mistake"; "suffered terrible thirst"
Antonym: good (indirect, via bad)
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