In the drawing, there’s nothing in the box (7)
I believe the answer is:
cartoon
'in the drawing' is the definition.
I can't tell whether this definition defines the answer.
'there's nothing in the box' is the wordplay.
'there's nothing' becomes 'o' (I've seen this in other clues).
'in the' means one lot of letters goes inside another.
'box' becomes 'carton' (carton is a kind of box).
'o' put into 'carton' is 'CARTOON'.
Can you help me to learn more?
(Other definitions for cartoon that I've seen before include "eg 'Tom & Jerry'" , "Drawing, maybe satirical" , "Humorous sketch" , "Jokey drawing" , "Comic drawing" .)