It's affected by tears - I cry loudly, by the sound of it! (7)
I believe the answer is:
eyeball
'it's affected by tears' is the definition.
I can't tell whether this definition defines the answer.
'i cry loudly by the sound of it' is the wordplay.
'i' becomes 'eye' (I've seen this in other clues).
'cry loudly' becomes 'bawl' (I've seen this in another clue).
'by the sound of it' indicates a 'sounds like' (homophone) clue.
'bawl' is a homophone of 'ball'.
'eye'+'ball'='EYEBALL'
Can you help me to learn more?
(Other definitions for eyeball that I've seen before include "Confront (_____ to _____)" , "Stare at closely; organ" , "Label ye (anag)" , "Ocular orb" , "It was cut in Un Chien Andalou" .)