a. 发嗡嗡声的, 声音低沉单调的

[ noun ]
an unchanging intonation
<noun.communication>

Drone \Drone\ (dr[=o]n), v. i. [imp. & p. p. {Droned}; p. pr. &
vb. n. {Droning}.] [Cf. (for sense 1) D. dreunen, G.
dr["o]hnen, Icel. drynja to roar, drynr a roaring, Sw.
dr["o]na to bellow, drone, Dan. dr["o]ne, Goth. drunjus
sound, Gr. ? dirge, ? to cry aloud, Skr. dhran to sound. Cf.
{Drone}, n.]
1. To utter or make a low, dull, monotonous, humming or
murmuring sound.

Where the beetle wheels his droning flight. --T.
Gray.

2. To love in idleness; to do nothing. ``Race of droning
kings.'' --Dryden.