Bob saves the traveller's time (5,3)
I believe the answer is:
short cut
'traveller's time' is the definition.
The definition suggests a singular noun which matches the answer.
'bob saves the' is the wordplay.
I cannot really understand how this works, but
'bob' could be 's' (abbreviation for shilling - 'bob' before 1971) and 's' is found in the answer.
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for short cut that I've seen before include "Means of saving time or effort" , "Time-saving route" , "Number one" , "Alternative route to save distance" , "Removal of most locks" .)