One may take it from its shell in a minute (3)
I believe the answer is:
nut
'one may take it from its shell' is the definition.
I can't tell whether this definition defines the answer.
'in a minute' is the wordplay.
'in' says the answer is hidden in the clue.
'NUT' is hidden within 'minute'.
Can you help me to learn more?
(Other definitions for nut that I've seen before include "eg Hazel" , "Hard kernel of minutiae" , "needing to get tight?" , "One securing bolt" , "Head; hard fruit" .)