In orderly way have meal, large, in New York (6)
I believe the answer is:
neatly
'in orderly way have meal large in new york' is the definition.
I can't tell whether this definition defines the answer.
'meal large in new york' is the wordplay.
'meal' becomes 'eat' (I can't explain this - if you can you should give a lot more credence to this answer).
'large' becomes 'L' (eg in clothes sizes).
'in' means one lot of letters goes inside another.
'new york' becomes 'ny'.
'eat'+'l'='eatl'
'eatl' going into 'ny' is 'NEATLY'.
Can you help me to learn more?
(Other definitions for neatly that I've seen before include "In tidy fashion" , "With deftness" , "Tidily and cleanly" , "Orderly and cleanly" , "In a tidy manner" .)