See dreadful in Webster's New World Roget's A-Z Thesaurus II
adjective
Causing or able to cause fear:
appalling, dire, direful, fearful, fearsome, formidable, frightful, ghastly, redoubtable, scary, terrible, tremendous. See fearVery bad:
appalling, awful, fearful, frightful, ghastly, horrendous, horrible, shocking, terrible. See good
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