Definition of "forky"

[…] for hungry birds have devoured ſeeds, and having moiſtened and warmed them in their bellies, a little after have dunged in the forky twiſtes of Trees, and together with their dung excluded the ſeed whole which erſt they had ſwallowed: and ſometimes it brings forth there where they dung it, […]

1669, John Baptiſta Porta, chapter V, in Natural Magick‎, The Third Book Of Natural Magick: […] , page 68

The Leaves are compoſed each of ſeven parts; the Flowers grow by two's on forky Footſtalks.

1764, John Hill, The Vegetable System. Or, The Internal Structure And The Life Of Plants; […] ‎, volume 7, page 32

The forky lightning flashed, and the deep toned thunder reverberated peal on peal, while the shrieking winds rocked the tree tops, and poured their wild melody upon the ear.

1857, Abigail Stanley Hanna, Withered Leaves from Memory's Garland‎

The column of fire now ascended above the main-top—licking with its forky tongue the top-mast rigging—and embracing the mainmast in its folds: […]

1896, Captain Frederick Marryat, The Phantom Ship‎

At the sight of the young man it lashed its tail so violently that the earth trembled as if with an earthquake, while its forky tongue darted in and out with a deafening hissing noise.

1921, Various, The Red Romance Book‎