The end is imminent (5)
I believe the answer is:
close
I believe this clue is a double definition.
'the end' is the first definition.
(I've seen this before)
'imminent' is the second definition.
('close' can be similar in meaning to 'imminent')
'is' acts as a link.
(Other definitions for close that I've seen before include "seal" , "Dense; nearby" , "nigh" , "residential street" , "Near, mean or humid" .)