Whence the train's guard can cry out, just in case (7)
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I believe the answer is:
caboose
'whence the train's guard can cry' is the definition.
I can't judge whether this defines the answer.
'just in case' is the wordplay.
'just' becomes 'boo' (I am not sure about this - if you are sure you should believe this answer much more).
'in' indicates putting letters inside.
'boo' placed into 'case' is 'CABOOSE'.
'out' acts as a link.
Can you help me to learn more?
(Other definitions for caboose that I've seen before include "American at the rear" , "US train crew's accommodation" , "Kitchen on ship's deck" .)
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