Dock for one minute close to overload (4)
I believe the answer is:
weed
'dock' is the definition.
(thesaurus)
'one minute close to overload' is the wordplay.
'one minute' becomes 'wee' (I've seen this before).
'close to' suggests the final letters (the close/ending of).
The last letter of 'overload' is 'd'.
'wee'+'d'='WEED'
'for' is the link.
(Other definitions for weed that I've seen before include "dope" , "Made water" , "gardening" , "nuisance in bed" , "gone!" .)