terrifyingly
/ˈtɛrɪfʌɪɪŋli
/adverb
In a way that causes extreme fear: the boat lurched terrifyingly [as submodifier]: viewers get terrifyingly close to the action...
- The only sound was our harsh breathing as we stared at Steve, who lay terrifyingly still.
- The strategy the High Command had adopted for fighting a probable two-front war was terrifyingly reckless.
- The most important lesson is that fire spreads terrifyingly quickly.