Inanimate, but it’s heard to croak at us (6)
I believe the answer is:
crocus
'inanimate but it's heard' is the definition.
I can't judge whether this defines the answer.
'croak at us' is the wordplay.
'croak at' becomes 'croc' (I am not sure about this - if you are sure you should believe this answer much more).
'croc'+'us'='CROCUS'
'to' is the link.
Can you help me to learn more?
(Other definitions for crocus that I've seen before include "Flower from which saffron is harvested" , "Small pretty spring flower, yellow or white" , "Yellow, purple or white spring flower" , "Plant from a corm" , "Occurs (anagram)" .)