I. Full of dread or fear.Full of respect, honor, or veneration.Exciting or attended by great dread, fear, or terror; terrible; formidable; direful: as, a dreadful storm; a dreadful invasion.Awful; venerable; awe-inspiring.Synonyms Fearful, Frightful, etc. (see awful); terrific, horrible, horrid, dire, direful, tremendous.n. That which is fearful or terrible: used only in the phrases penny dreadful, shilling dreadful, to denote a tale of vulgar sensationalism sold at a small price, or a cheap sensational newspaper or periodical.