Short for
quintuplets.
This is notable, because it is really the only shortened version of a term for multiple offspring of a single birth; you never hear "octs" instead of "octuplets", or "sexes" instead of "sextuplets". You might occasionally hear "quads" instead of "quadruplets", but very rarely.
Of course, there are only about 20 sets of quints born every year (to human parents, anyway - puppies, hamsters, and such, come in fives all the time!), so it's not like you really hear either "quints" or "quintuplets" all that often, anyway.
But, if you're not one of the lucky(?) parents of quintuplets, you might consider dropping $1,495.00 plus $15.00 Shipping and Handling, for Misty, Star Bright, Twinkle Toes, Sunny, and Twilight, the "Millennium Quints" dolls , each lovingly crafted by Linda Lee Sutton, available at
http://www.fun-a-fair.com/lindaleesutton/millennium_quints_porcelain_doll.htm
Now, if $1500 is a little out of your price range, Tyco Toys mass-produced it's own "Quints" toy line, from about 1989 to 1995, so while you can't find them on the shelves of your local Toys-R-Us, you should be able to get a set on Ebay for less than $50. (as of right now - tomorrow, who knows?)
Oh, you're not quite that obsessive? How about checking out one of the biographies of the Dionne Quintuplets, born in Canada, in 1934? (They were actually immortalized in doll form, themselves; I guess there's no escaping dolls, in the realm of oh-so-cute quints...)