Sent us out at the end of the day (6)
I believe the answer is:
sunset
'the end of the day' is the definition.
(I've seen this before)
'sent us out' is the wordplay.
'out' is an anagram indicator (out can mean wrong or inaccurate).
'sent'+'us'='sentus'
'sentus' is an anagram of 'SUNSET'.
'at' is the link.
(Other definitions for sunset that I've seen before include "Final declining phase (of something)" , "Dusk" , "'The dying of the 18'" , "Evening glow" , "Nightfall" .)