Model soldier first to march on trench (8)
I believe the answer is:
paradigm
'model' is the definition.
(I know that paradigm is a type of model)
'first to march on trench' is the wordplay.
'first to' suggests taking the first letters.
'on' means one lot of letters go next to another.
'trench' becomes 'paradig' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
The first letter of 'march' is 'm'.
'm' put after 'paradig' is 'PARADIGM'.
'soldier' is the link.
Can you help me to learn more?
(Other definitions for paradigm that I've seen before include "Archetype" , "Epitome" , "Typical example or pattern" , "Example or explanatory model" , "Adam grip (anag.)" .)