Woeful word (4)
I believe the answer is:
alas
'woeful word' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for alas that I've seen before include "woebegone expression" , "Cry of regret" , "Proper, respectable" , "Archaic exclamation of sorrow or regret" , "Exclamation of grief" .)