Lazy person finished round middle of afternoon (5)
I believe the answer is:
drone
'lazy person' is the definition.
(drone can mean someone who drones on boringly)
'finished round middle of afternoon' is the wordplay.
'finished' becomes 'done' (similar in meaning).
'round' is an insertion indicator.
'middle of' means to look at the middle letters.
The middle letter of 'afternoon' is 'r'.
'done' going around 'r' is 'DRONE'.
(Other definitions for drone that I've seen before include "Monotonous sound - member of hive" , "Continuous sound; bee" , "Talk boringly; male bee" , "Male bee - monotonous hum" , "talk long and tediously" .)