the.com/hobby
What you do for love instead of money, then somehow spend money on.
means An activity pursued for pleasure in your free time, with no obligation to be good at it.
from Short for hobby-horse, the wooden toy horse children straddled to play at riding — by the 1800s, riding your hobby-horse meant chasing a harmless private pastime.
Original toyA stick with a fake horse head.
Hobbit echoTolkien's name shares the same playful old root.
Idiom survivorHobby-horse still means a pet obsession.