Glop'pen (glŏp'p e n) transitive verb & i. [ Middle English glopnen to be frightened, frighten: confer Icelandic glūpna to look downcast.] To surprise or astonish; to be startled or astonished. [ Prov. Eng.] Halliwell. Found on http://www.encyclo.co.uk/webster/G/35