Source : Webster's Revised Unabridged Dictionary (1913)

Gloppen \Glop"pen\, v. t. & i. [OE. glopnen to be frightened,
   frighten: cf. Icel. gl?pna to look downcast.]
   To surprise or astonish; to be startled or astonished. [Prov.
   Eng.] --Halliwell.