Lonely female mislaid hat (5)
I believe the answer is:
beret
'hat' is the definition.
(I've seen this before)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for beret that I've seen before include "Round, brimless cap" , "French flat hat" , "cap in France?" , "Soft brimless cap" , "Kind of floppy cap with no peak" .)