IPA: /ˈdroʊnɪŋli/
KK: /ˈdroʊnɪŋli/
In a way that produces a low, continuous, monotonous sound.
The teacher spoke droningly, making it hard for the students to stay awake.
Droningly → It is formed from "drone" (from Old English *drān*, meaning a low, continuous sound) and the suffix "-ly" (meaning in a manner). The word "droningly" describes the manner of making a low, continuous sound, often in a monotonous way.
Think of a 'drone' making a low, continuous sound, and remember that 'droningly' means doing something in that monotonous manner.