Promote bath accessory (4)
I believe the answer is:
plug
This might be a double definition.
'promote' is the first definition.
(I know that plug is a kind of promote)
'bath accessory' is the second definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe there's an association between them I don't understand?
Can you help me to learn more?
(Other definitions for plug that I've seen before include "Publicise -- stop" , "Stopper - connector" , "Power point" , "Bath or sink stopper" , "Mention favourably - stopper" .)