Remain second best (4)
I believe the answer is:
Here is my best explanation:
'remain' is the definition.
The answer and definition can be both related to change as well as being verbs in their base form.
Maybe there's a link between them I don't understand?
'second best' is the wordplay.
'second' becomes 's' (common abbreviation).
'best' becomes 'top' (associated in meaning).
Can you help me to learn more?