Genuine card found by individual on holiday (3-3)
I believe the answer is:
one-off
'genuine card' is the definition.
The definition suggests a singular noun which matches the answer.
'by individual on holiday' is the wordplay.
'by' says to put letters next to each other.
'individual' becomes 'one' (**).
'on holiday' becomes 'off' (I've seen this before).
'one' next to 'off' is 'ONE-OFF'.
'found' is the link.
Can you help me to learn more?
(Other definitions for one-off that I've seen before include "Happening only once" , "A single event, not reproduced or repeated" , "Unrepeatable experience" , "Made as single article, not repeated" , "Unique specimen" .)