Casual greeting delivered louder (6)
I believe the answer is:
higher
'louder' is the definition.
Both the answer and definition are comparative adjectives. Perhaps you can see a link between them that I don't see?
'casual greeting delivered' is the wordplay.
'casual greeting' becomes 'hiya' (I've seen this in another clue).
'delivered' shows a homophone (sound like) (delivered verbally).
'hiya' is a homophone of 'HIGHER'.
Can you help me to learn more?
(Other definitions for higher that I've seen before include "More lofty" , "More exalted" , "Superior or taller" , "Loftier" , "At greater altitude" .)