I. ˈspük noun
Etymology: Dutch; akin to Middle Low German spōk ghost
Date: 1801
1. : ghost , specter
2. : an undercover agent : spy
• spook·ish ˈspü-kish adjective
II. verb
Date: 1883
transitive verb
1. : haunt 3
2. : to make frightened or frantic : scare ; especially : to startle into violent activity (as stampeding)
intransitive verb
: to become spooked
cattle spook ing at shadows