spookish

spook +‎ ish

spookish (comparative more spookish, superlative most spookish)

1. (informal) Frightening or unnerving in the manner of something eerie or supernatural; spooky.
   • 1914, Edward Stratemeyer, chapter 22, in Dave Porter in the Gold Fields:

     I hope we find some nicer spot than this. This looks so lonely and spookish.

   • 1930, H. L. Mencken, Treatise on the Gods, published 2006, →ISBN, pages 174–5:

     Religion is everywhere a gauge of respectability. . . . The right to participate, however humbly, in His august and transcendental operations offers a powerful satisfaction to the will to power; the same privilege, on a smaller scale, is what takes hordes of human blanks into the Freemasons and other such spookish amalgamations of nonentities.

2. (informal, often of a horse or other animal) Easily startled, frightened, or unnerved.
   • 1908, Sylvester Barbour, Reminiscences, published 2009, →ISBN, page 26:

     In those moments thus spent in composing myself for sleep, I sometimes wondered in the last human occupant of the room were not a dead one. I was senselessly spookish about such things.

   • 2010, “Sarah $3000”, in isoldmyhorse.com, retrieved 13 July 2010:

     As a lesson horse she needs to gain confidence in her rider, or can become spookish over the jumps, dodging out of them.

• (easily startled or frightened): skittish

• Oxford English Dictionary, 2nd ed., 1989.