Adjective dreadful has 3 senses
- awful, dire, direful, dread, dreaded, dreadful, fearful, fearsome, frightening, horrendous, horrific, terrible - causing fear or dread or terror; "the awful war"; "an awful risk"; "dire news"; "a career or vengeance so direful that London was shocked"; "the dread presence of the headmaster"; "polio is no longer the dreaded disease it once was"; "a dreadful storm"; "a fearful howling"; "horrendous explosions shook the city"; "a terrible curse"
Antonym: unalarming (indirect, via alarming)
- atrocious, abominable, awful, dreadful, painful, terrible, unspeakable - exceptionally bad or displeasing; "atrocious taste"; "abominable workmanship"; "an awful voice"; "dreadful manners"; "a painful performance"; "terrible handwriting"; "an unspeakable odor came sweeping into the room"
Antonym: good (indirect, via bad)
- dreadful - very unpleasant
Antonym: pleasant (indirect, via unpleasant)
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