Happening I'd note, arriving at close of day (8)
I believe the answer is:
eventide
'close of day' is the definition.
(thesaurus)
'happening i'd note' is the wordplay.
'happening' becomes 'event' (I've seen this before).
'note' becomes 'e' (musical note).
'event'+'id'+'e'='EVENTIDE'
'arriving at' is the link.
(Other definitions for eventide that I've seen before include "sunset" , "when it starts to get dark" , "late in the day?" , "End of the day to the poet" , "The day's close (poetic)" .)