- hobbyhorse - a topic to which one constantly reverts; "don't get him started on his hobbyhorse"
--1 is a kind of preoccupation
- hobby, hobbyhorse, rocking horse - a child's plaything consisting of an imitation horse mounted on rockers; the child straddles it and pretends to ride
--2 is a kind of plaything, toy
--2 has parts: rocker - hobby, hobbyhorse, rocking horse - a child's plaything consisting of an imitation horse mounted on rockers; the child straddles it and pretends to ride