Wrap last sub, order first one (3)
I believe the answer is:
boa
'wrap' is the definition.
(I've seen this in another clue)
'last sub order first one' is the wordplay.
'last' says to take the final letters.
'order first' becomes 'o' (1st letter of 'order').
'one' becomes 'a' (a thing is one thing).
The final letter of 'sub' is 'b'.
'b'+'o'+'a'='BOA'
(Other definitions for boa that I've seen before include "Large reptile" , "Potential killer" , "One with scaly body" , "Feathered neckwear - snake" , "Fluffy scarf of feathers" .)