as per usual, Marty, never say never...

4. A stick with a horse's head which children bestride as a toy horse.
b. A wooden horse fixed on a ‘merry-go-round’ at a fair. c. A rocking-horse for the nursery.

1741 Gray Let. Poems (1775) 114 A Fair here is not a place where one eats gingerbread or rides upon hobby-horses. 1842 S. C. Hall Ireland II. 340 The merry-go-rounds and hobby-horses ‘crammed’. [OED - I'm going to petition Anu and his next 'chat' guest for an OED icon]