Moth in tree, for example, travelling both ways, right? (3,5)

'example travelling both ways right?' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.

'moth in tree' is the wordplay.
I cannot really see how this works, but
'moth' could be 'egger' (egger is a kind of moth) and 'egger' is found within the answer.
'tree' could be 'oak' (oak is a type of tree) and 'oak' is present in the answer.
This accounts for all the letters.
This explanation may well be incorrect...

'for' acts as a link.

Can you help me to learn more?