Don't waste time coming from Athens (6)
I believe the answer is:
hasten
'don't waste time coming from athens' is the definition.
I can't tell whether this defines the answer.
'from athens' is the wordplay.
'from' indicates an anagram (from the letters).
'athens' with letters rearranged gives 'HASTEN'.
Can you help me to learn more?
(Other definitions for hasten that I've seen before include "race? - with 26a" , "Speed up" , "Athens (anag.)" , "Act or move fast" , "Hurry along" .)