Beautiful cab caught (8)
I believe the answer is:
handsome
'beautiful' is the definition.
(similar in meaning)
'cab caught' is the wordplay.
'cab' becomes 'hansom' (I've seen this in another clue).
'caught' indicates a 'sounds like' (homophone) clue (heard).
'hansom' is a homophone of 'HANDSOME'.
(Other definitions for handsome that I've seen before include "Pleasing in appearance" , "beautiful" , "large" , "Good-looking, as a male say" , "Fit" .)