Hi-fi component required for one posting messages (7)
I believe the answer is:
tweeter
This clue could be a double definition.
'hi-fi component' is the first definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe you can see an association between them that I can't see?
'one posting messages' is the second definition.
Although both the answer and definition are singular nouns, I cannot understand how they can define each other.
'required for' is the link.
Can you help me to learn more?
(Other definitions for tweeter that I've seen before include "little Speaker" , "High-frequency speaker" , "Message sender" , "Person sending a messages of fewer than 140 characters" , "High-frequency loudspeaker - small bird?" .)