Getting into three-wheel car I measured up is a marvel (7)
I believe the answer is:
miracle
'a marvel' is the definition.
(thesaurus)
'getting into three-wheel car i measured up' is the wordplay.
'getting into' indicates a hidden word.
'up' says the letters should be written in reverse (in down clue: letters go upwards).
'elcarim' is hidden within 'three wheel car i measured'.
'elcarim' backwards is 'MIRACLE'.
'is' acts as a link.
(Other definitions for miracle that I've seen before include "Wonder, sign" , "Supernatural happening" , "Supernatural occurrence" , "Amazing event" , "Divine action" .)