Capital of Turkmenistan erased from geography book, woe is me! (4)
I believe the answer is:
alas
'woe is me' is the definition.
(I've seen this in another clue)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for alas that I've seen before include "I'm sorry to say" , "Regretfully!" , "Interjection of sorrow" , "-- and alack!" , "Unhappily" .)