How unusual to find the motorway clear! (7)
I believe the answer is:
miracle
'how unusual to find' is the definition.
I can't tell whether this defines the answer.
'motorway clear' is the wordplay.
I cannot quite see how this works, but
'motorway' could be 'mi' (resembles M1, English motorway) and 'mi' is found in the answer.
an anagram of 'clear' is 'racle' which is located in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
'the' is the link.
Can you help me to learn more?
(Other definitions for miracle that I've seen before include "Supernatural happening" , "Divine action" , "Amazing or unexplained occurrence" , "Wonder, sign" , "God-inspired event" .)