IPA: /ˈbrɛθˌteɪkɪŋli/
KK: /ˈbrɛθˌteɪkɪŋli/
In a way that is extremely impressive or beautiful, causing a feeling of awe or wonder.
The view from the mountain was breathtakingly beautiful at sunset.
Breathtakingly → It is formed from "breathe" (from Old English "brēath", meaning to take in air) and "-taking" (from the verb "take", meaning to grasp or seize) combined with the adverbial suffix "-ly" (meaning in a manner of). The word "breathtakingly" describes something done in a manner that seizes one's breath, often due to beauty or awe.
Think of the act of 'breathing' being 'seized' or taken away by something amazing — that's why breathtakingly means in a way that takes your breath away.