What does "hobbyhorse" mean?

Hobbyhorse: A stick, often with the head or figure of a horse, on which boys make believe to ride. [ Usually under the form hobbyhorse.]

Additional senses

  1. 2.A subject or plan upon which one is constantly setting off; a favorite and ever-recurring theme of discourse, thought, or effort; that which occupies one's attention unduly, or to the weariness of others; a ruling passion. [Usually under the form hobby.] Not one of them has any hobbyhorse, to use the phrase of Sterne. Macaulay.

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