A shortage, sad to say (5)

I believe the answer is:

alack

'sad to say' is the definition.

'a shortage' is the wordplay.
'shortage' becomes 'lack' (a lack is a shortage of something).
'a'+'lack'='ALACK'

(Other definitions for alack that I've seen before include "expression of regret" , "Sadly" , "Old expression of dismay" , "Previously expressed regret" , "I mourn" .)

I've seen this clue in The Globe and Mail.

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