Hastened, like one getting out of the rain (3)
I believe the answer is:
ran
'hastened' is the definition.
(I've seen this before)
'one getting out of the rain' is the wordplay.
'one' becomes 'I' (Roman numeral).
'getting out of' suggests deleting specific letters.
'rain' with 'i' taken out is 'RAN'.
'like' acts as a link.
(Other definitions for ran that I've seen before include "Entered (a race)" , "Tore" , "Managed; raced" , "Hastened" , "11 on foot" .)