Describing certain atoms, is oxygen at issue? (8)
I believe the answer is:
isotopic
'describing certain atoms is oxygen at issue?' is the definition.
I can't judge whether this definition defines the answer.
'is oxygen at issue?' is the wordplay.
'oxygen' becomes 'O' (atomic symbol for oxygen).
'at' is a charade indicator (letters next to each other).
'issue?' becomes 'topic' ('topic' can be a synonym of 'issue').
'is'+'o'+'topic'='ISOTOPIC'
Can you help me to learn more?
(Other definitions for isotopic that I've seen before include "Like different forms of the same element" , "like some atoms" , "Relating to different forms of an element" .)