Crossword Genius

Diana's engagement is a let-down (14)

Ross

I believe the answer is:

disappointment

'a let-down' is the definition.
(I've seen this before)

'diana's engagement' is the wordplay.
'diana's' becomes 'Di's' (Di is short for Diana).
'engagement' becomes 'appointment' (synonyms).
'dis'+'appointment'='DISAPPOINTMENT'

'is' is the link.

(Other definitions for disappointment that I've seen before include "Setback" , "Frustration" , "Frustrating thing" , "Let-down" , "unhappiness" .)

I've seen this clue in The Guardian.
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