Unassuming fashion on the way (6)
I believe the answer is:
modest
'unassuming' is the definition.
(similar in meaning)
'fashion on the way' is the wordplay.
'fashion' becomes 'mode' (synonyms).
'on' means one lot of letters go next to another (in a down clue, letters appear on others).
'the way' becomes 'st' (abbreviation for street).
'mode'+'st'='MODEST'
(Other definitions for modest that I've seen before include "Not boastful" , "Free from pomp or affectation" , "Having a humble opinion of oneself" , "Lacking vanity" , "Bashful" .)