Fail to find motorway covering Scottish island (6)
I believe the answer is:
mislay
'fail' is the definition.
Although both the answer and definition are verbs in their base form, I don't see how one could define the other.
'motorway covering scottish island' is the wordplay.
'motorway' becomes 'm'.
'covering' says to put letters next to each other (on top of in down clue).
'scottish island' becomes 'islay' (I've seen this before).
'm'+'islay'='MISLAY'
'to find' is the link.
Can you help me to learn more?
(Other definitions for mislay that I've seen before include "Put (something) where it can't be found" , "Put in wrong place, lose temporarily" , "Set in wrong location" , "Be unable to find" , "Lose (an item)" .)