Sport involving maps says to turn earring to the east (12)
I believe the answer is:
orienteering
'sport involving maps says to turn earring to' is the definition.
I can't tell whether this definition defines the answer.
'east' is the wordplay.
I cannot quite understand how this works, but
'east' could be 'orient' (synonyms) and 'orient' is found in the answer.
This explanation may well be incorrect...
'the' is the link.
Can you help me to learn more?
(Another definition for orienteering that I've seen is " Sport using map and compass".)