Single now? Aye, after a fashion! (3-3)
I believe the answer is:
one-way
'single' is the definition.
(as in a single train ticket)
'now? aye after a fashion' is the wordplay.
'after a fashion' is an anagram indicator (letters re-fashioned).
'now'+'aye'='nowaye'
'nowaye' is an anagram of 'ONE-WAY'.
(Other definitions for one-way that I've seen before include "Allowing motion in a single direction" , "Type of travel ticket" , "This street allows only single traffic flow" , "Unidirectional" , "Street allowing traffic in single direction only" .)