Shortened from hobby-horse, from Middle English hoby, hobyn, hobin (“small horse, pony”), from Old French hobi, *haubi, haubby, hobin ("a nag, hobby"; > Modern French aubin, Italian ubino), of Germanic origin: from Old French hober, ober (“to stir, move”), from Old Dutch hobben (“to toss, move up and down”); or from North Germanic origin related to Danish hoppe (“a mare”), Old Swedish hoppa (“a young mare”), North Frisian hoppe (“horse”); both ultimately from Proto-Germanic *huppōną (“to hop”), from Proto-Indo-European *kewb- (“to bend; a bend, joint”). More at hop, hobble. The meaning of hobby-horse shifted from "small horse, pony" to "child's toy riding horse" to "favorite pastime or avocation" with the connecting notion being "activity that doesn't go anywhere". Possibly originally from a proper name for a horse, a diminutive of Robert or Robin (compare dobbin).
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An activity that one enjoys doing in one's spare time.
I like to collect stamps from different countries as a hobby.
take up a hobby
1 more example
give up your hobby
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Equestrianism, Hobbies, Horses, Lifestyle, Pets, Sports An extinct breed of horse native to the British Isles, also known as the Irish Hobby.
I was out a-hunting to-day, and I got away to a place in the wood I’d never seen before. And there was an old chalk-pit. And I heard a kind of a sort of humming. So I got off my hobby, and I went right quiet to the pit, and I looked down.1890, Joseph Jacobs, “Tom Tit Tot”, in English Fairy Tales, page 7:
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Synonym of hobby horse (“a favorite topic”).
"Well, I think East is right," said Arthur; "I can't see but what it's right to do the best you can, though it mayn't be the best absolutely. Every man isn't born to be a martyr." "Of course, of course," said East; "but he's on one of his pet hobbies. — How often have I told you, Tom, that you must drive a nail where it'll go."1857, Thomas Hughes, Tom Brown's School Days:
Etymology From Middle English hoby, hobeye, from Old French hobé, hobei, hobet, from Medieval Latin hopētus, diminutive of harpe.
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Any of four species of small falcons in the genus Falco, especially Falco subbuteo.
He hawked – from nearby Esher, Richard Fox sent a servant with a hobby, which Henry received enthusiastically – and hunted, sending a present of freshly slaughtered deer to Princess Mary.2011, Thomas Penn, Winter King, Penguin, published 2012, page 323: