Stop row about when you will show up (6)

I believe the answer is:

detain

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

I don't understand how the remainder of the clue works.

(Other definitions for detain that I've seen before include "Keep waiting or under restraint" , "Keep in custody or delay" , "Keep in official custody" , "Stop" , "Hold (someone) back" .)

I've seen this clue in The Irish Times.

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