Go off course, say about two-fifths of a metre (5)
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I believe the answer is:
stray
'go off course' is the definition.
(I've seen this in another clue)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for stray that I've seen before include "Depart from the right path" , "Appearing occasionally" , "Wander off course" , "Drift - isolated" , "Deviate" .)
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