It's heard that the Poles are going to central Korea (5)
I believe the answer is:
snore
'it's heard that' is the definition.
I can't judge whether this defines the answer.
'poles are going to central korea' is the wordplay.
'poles' becomes 'SN' (North and South poles).
'are going to' says to put letters next to each other.
'central' says to take the centre.
The middle letters of 'korea' are 'ore'.
'sn'+'ore'='SNORE'
'the' is the link.
Can you help me to learn more?
(Other definitions for snore that I've seen before include "Noise from a sleeper" , "Breathe noisily during sleep" , "thing which bores" , "How to keep someone awake while sleeping?" , "Make raucous nocturnal noise" .)