Aptitude one acquires by often being in the way (4,5)
I believe the answer is:
road sense
'aptitude one' is the definition.
Although both the answer and definition are singular nouns, I don't understand how they can define each other.
'by often being in the way' is the wordplay.
I cannot quite see how this works, but
'being' could be 'ens' (philosophical term for being or existence) and 'ens' is found in the answer.
'way' could be 'road' (road is a kind of way) and 'road' is located in the answer.
The remaining letters 'se' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'acquires' is the link.
Can you help me to learn more?
(Other definitions for road sense that I've seen before include "Driver should display this" , "Driving schools teach this" , "Driving skill" , "traffic awareness" , "Driver's good judgment" .)