Serious listener with place for birds (7)
I believe the answer is:
earnest
'serious' is the definition.
(similar in meaning)
'listener with place for birds' is the wordplay.
'listener' becomes 'ear' (body part which hears or listens).
'with' is a charade indicator (letters next to each other).
'place for birds' becomes 'nest' (I am not sure about this - if you are sure you should believe this answer much more).
'ear'+'nest'='EARNEST'
Can you help me to learn more?
(Other definitions for earnest that I've seen before include "Grave" , "Seriously eager" , "Determined - heartfelt" , "Serious, intent" , "'Serious, sincere (7)'" .)