Second mark of approval (4)

I believe the answer is:

tick

I believe this is a double definition.

'second' is the first definition.
(I've seen this before)

'mark of approval' is the second definition.
(I've seen this before)

(Other definitions for tick that I've seen before include "Not cross" , "credit > check" , "Arrangement for deferred payment" , "Small parasitic arachnid" , "Blood-sucking arachnid" .)

I've seen this clue in The Telegraph.

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