Old toy, among other things, contains boat (4,1,6)
I believe the answer is:
etch a sketch
Here is my best explanation:
'old toy' is the definition.
'among other things contains boat' is the wordplay.
'among other things' becomes 'etc'.
'contains' becomes 'has' (I've seen this before).
'boat' becomes 'ketch' (ketch is a kind of sailing vessel).
'etc'+'has'+'ketch'='ETCH A SKETCH'