Definition of "mizzen"

Finding it was like to overblow, we took in our Sprit-ſail, and ſtood by to hand the Fore-ſail; but making foul Weather, we look'd the Guns were all faſt, and handed the Miſſen.

1726 October 28, [Jonathan Swift], “A Great Storm Described, the Long-Boat Sent to Fetch Water, the Author Goes with It to Discover the Country. […]”, in Travels into Several Remote Nations of the World. […] [Gulliver’s Travels], volume I, London: […] Benj[amin] Motte, […], part II (A Voyage to Brobdingnag), page 151

"'Oh yes, that's all very well, but we haven't done with it yet,' said the lad, 'we shall have it worse directly,' and he ordered them to furl every rag but the mizen."

1886, Peter Christen Asbjørnsen, translated by H.L. Brækstad, Folk and Fairy Tales, page 191