Circuits have direction to go downhill (5)
I believe the answer is:
lapse
'go downhill' is the definition.
(thesaurus)
'circuits have direction' is the wordplay.
'circuits' becomes 'laps' ('lap' can be a synonym of 'circuit').
'have' means one lot of letters go next to another.
'direction' becomes 'e' (E is an example).
'laps'+'e'='LAPSE'
'to' acts as a link.
(Other definitions for lapse that I've seen before include "Loss (in concentration, say?)" , "Run out" , "Temporary drop in standard" , "Inadvertent error" , "Slight error due to forgetfulness" .)