Soldier, nod off (8)

I believe the answer is:
commando
'soldier' is the definition.
(I've seen this before)
'nod off' is the wordplay.
I cannot quite understand how this works, but
an anagram of 'nod' is 'ndo' which is present in the answer.
The remaining letters 'comma' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for commando that I've seen before include "A specially trained soldier" , "Kilt-wearer might go" , "Soldier trained for carrying out raids" , "Amphibious military unit" , "Green Beret" .)
