Came across first fruit to fall (7)
I believe the answer is:
plummet
'fall' is the definition.
(plummet is a kind of fall)
'came across first fruit' is the wordplay.
'came across' becomes 'met' ('meet' can be a synonym of 'come across').
'first' says to put letters next to each other.
'fruit' becomes 'plum' (plum is a kind of fruit).
'met' after 'plum' is 'PLUMMET'.
'to' acts as a link.
(Other definitions for plummet that I've seen before include "Drop sharply" , "Descend" , "Fall at high speed" , "Plunge headlong" , "Fall like a stone" .)