Lacking caution in endeavour — a shame (4)

I believe the answer is:

rash

'lacking caution' is the definition.

'in endeavour a shame' is the wordplay.
'in' says the answer is hidden in the clue.
'RASH' can be found hidden inside 'endeavour a shame'.

(Other definitions for rash that I've seen before include "Unwisely incurring danger" , "Foolhardy about the skin infection" , "Precipitate" , "Eruption of spots on skin" , "Lacking in caution" .)

I've seen this clue in The Times.

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