Meaning

adjective exceptionally bad or displeasing

adjective causing fear or dread or terror

adjective offensive or even (of persons) malicious; ; ; ; ; ; - Ezra Pound

originFrom Middle English agheful, awfull, auful, aȝefull, equivalent to awe + -ful. Compare Old English eġeful, eġefull (“terrifying; awful”). The “very bad” sense is a pejorative semantic shift from the original sense of “awe-inspiring”.

Etymology from Wiktionary, CC BY-SA 3.0