“The word ‘awful’ traces back to the Old English root ege, meaning dread, reverence or profound respect,” Sophie Vignoles, a linguist and head of learning content at the language learning app Babbel, told HuffPost. “That origin shows in its early use. It originally meant something that filled you with awe, describing anything that inspired wonder or terror, often tied to the power of God or nature, and it was a compliment. A mountain range or a storm could be called awful, and that was high praise.”
Article source: https://www.huffingtonpost.co.uk/entry/awful-origin_uk_6a86f9d0e4b0e9f1dd27a21d