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.
A hobby is a fairly small, very swift falcon with long, narrow wings. There are four birds called hobby, and three others which, although termed falcon, are very similar. All specialise in catching prey on the wing.
Income from a hobby is not taxable and related expenses are not allowable. There are criteria to differentiate between a business and a hobby. If in doubt, contact the Inland Revenue, accountant or Tax Advisor.