IPA: /ˈfɪəfəl/
KK: /ˈfɪrfl/
Feeling afraid or scared; also describes something that causes fear.
The fearful child hid behind his mother during the thunderstorm.
Comparative: more fearful
Superlative: most fearful
Fearful → It is formed from "fear" (from Old English "fǣr", meaning a feeling of anxiety or dread) and "-ful" (meaning full of). The word "fearful" means full of fear or feeling afraid.
Think of feeling 'full of fear' — that's what 'fearful' means.