Answer: ahum

AnswerCrossword Clue
AHUM

Buzzing

AHUM

Super-busy

AHUM

Buzzing with activity

AHUM
Busy, in a way
AHUM
Extremely busy
AHUMWhirring.
AHUMBee-loud.
AHUMBuzzing.
AHUMBustling with activity.
AHUMLike a beehive.
AHUMBusy.
AHUMNoisily busy
AHUMAudibly active
AHUMLike a beehive