Woman in train perked up? Tummy calmer (8)
I believe the answer is:
magnesia
'train perked up? tummy calmer' is the definition.
I can't tell whether this definition defines the answer.
'woman' is the wordplay.
I cannot quite understand how this works, but
'woman' could be 'agnes' and 'agnes' is located in the answer.
The remaining letters 'mia' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
'in' is the link.
Can you help me to learn more?
(Other definitions for magnesia that I've seen before include "Asian gem (anag) - milk of ___" , "laxative" , "Medicinal powder" , "Carbonate used as an antacid" , "Is Ma easing off the white mineral?" .)