Underweight babies in the army? (5,8)
I believe the answer is:
light infantry
'the army?' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.
'underweight babies' is the wordplay.
'underweight' becomes 'light'.
'babies' becomes 'infantry' (I can't justify this - if you can you should believe this answer much more).
'light'+'infantry'='LIGHT INFANTRY'
'in' is the link.
Can you help me to learn more?
(Other definitions for light infantry that I've seen before include "Former British Army regiment" , "Highly manoeuvrable soldiers" , "Mobile foot soldiers" .)