In some way, it's possibly belted (5)
I believe the answer is:
waist
'in some way it's possibly belted' is the definition.
I can't tell whether this definition defines the answer.
'in some way it's possibly' is the wordplay.
'in some way' becomes 'wa' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'possibly' is an anagram indicator.
'its' with letters rearranged gives 'ist'.
'wa'+'ist'='WAIST'
Can you help me to learn more?
(Other definitions for waist that I've seen before include "Spare tyre location?" , "Midriff" , "Middle of trunk" , "part of frame" , "Between ribs and hips" .)