IPA: /ˈwɪspərɪŋli/
KK: /ˈhwɪspərɪŋli/
In a way that is quiet and soft, often used to speak without being heard by others.
She spoke whisperingly so that no one else could hear their conversation.
Whisperingly → It is formed from "whisper" (from Old English *hwisprian*, meaning to speak softly) and the suffix "-ingly" (meaning in a manner of). The word "whisperingly" means in a manner that involves speaking softly or quietly.
Imagine speaking softly, as if sharing a secret, which helps you remember that "whisperingly" means to do so in a soft manner.