Robot dog almost eats young boy at first (6)
I believe the answer is:
cyborg
'robot dog almost' is the definition.
I know nothing about this answer so I cannot judge whether this works.
'eats young boy at first' is the wordplay.
'eats young' becomes 'borg' (I can't justify this - if you can you should give a lot more credence to this answer).
'boy' becomes 'Cy'.
'at first' is a charade indicator (letters next to each other).
'borg' after 'cy' is 'CYBORG'.
Can you help me to learn more?
(Other definitions for cyborg that I've seen before include "Bionic person - bog cry (anag)" , "Robot made of biological and machine parts" , "Bionic man (or woman)" , "Human whose body has been taken over by manmade devices" , "Human enhanced by mechanical elements" .)