aw·ful [áwf’l] adjective 1. extremely bad: very bad or unpleasant an awful smell 2. causing shock or sadness: extremely shocking, saddening, or unpleasant an awful accident 3. sick: in poor health I feel awful this morning. 4. very great: enormous in size, amount, number, or extent (informal) We spent an awful lot of money on furniture. 5. awe-inspiring: so impressive as to inspire awe (literary) adverb extremely: to an extreme degree or extent (informal) It’s awful hot this morning. [13th century. < awe1] -aw·ful·ness, noun