Definition of Dreadful

Adjective: dreadful dred-ful

Causing fear, dread or terror
"a dreadful storm";
- awful, dire, direful, dread, dreaded, fearful, fearsome, frightening, horrendous, horrific, terrible
Exceptionally bad or displeasing
"dreadful manners";
- atrocious, abominable, awful, painful, terrible, unspeakable, horrible
Very unpleasant