thrum
thrum /θr'ʌm/ (thrums thrumming thrummed)
[VERB] V
When something such as a machine or engine thrums, it makes a low beating sound.
The air-conditioner thrummed.
[N-COUNT; SOUND]
Thrum is also a noun.
...the thrum of refrigeration motors...
My head was going thrum thrum thrum.
[VERB] V
When something such as a machine or engine thrums, it makes a low beating sound.
The air-conditioner thrummed.
[N-COUNT; SOUND]
Thrum is also a noun.
...the thrum of refrigeration motors...
My head was going thrum thrum thrum.