Definition of "grapnel"

[…] we espied towards the North end of the Iland ye light of a great fire thorow the woods, to the which we presently rowed: when wee came right ouer against it, we let fall our Grapnel neere the shore, & sounded with a trumpet a Call […]

1589, Richard Hakluyt, The Principall Navigations, Voiages, and Discoveries of the English Nation, […], London: […] George Bishop and Ralph Newberie, deputies to Christopher Barker, […], page 292

At dawn of day we got on shore, and tracked the boat into shelter; for the wind blowing fresh without, and the ground being rocky, I was afraid to trust her at a grapnel, lest she might be blown to sea: I was, therefore, obliged to let her ground in the course of the ebb.

1790, William Bligh, A Narrative of the Mutiny on Board his Majesty’s Ship Bounty, London: George Nicol, Entry for 1 June, 1789

[…] the wind dying away, the signal was made for casting anchor, when both ships came to in 26 fathom water; but the Resolution expecting to come to with her small stream anchor, let the whole run out, and lost both anchor and hauser, besides the ship’s grapnel in looking for it.

1785, John Rickman, Journal of Captain Cook’s Last Voyage to the Pacific Ocean‎, London: E. Newbery, Part II, p. 233

With anxious grapnels I had sounded my pocket, and only brought up a few pieces of silver ...

1851, Herman Melville, Moby Dick, Chapter 2

“ […] Why, you’ve flung your grapnel over the doctor, and he’s coming courting forthwith.”

1886 May – 1887 April, Thomas Hardy, “chapter 22”, in The Woodlanders […], volumes (please specify |volume=I to III), London, New York, N.Y.: Macmillan and Co., published 1887

But by the mercy o’ God to heretics, what were left o’ my poor ship got a hold on that guarda-costa’s timbers wi’ her grapnels, what time we climbs aboard her.

1936, Rafael Sabatini, “Sacrilege”, in The Fortunes of Captain Blood‎