The Proto-Indo-European word *dwei-
Word *dwei-
Meaning fear
See also Proto-Indo-European: *dwéh₃(u) ‘two’
Synonyms *gʰouro-, *kʷeh₁(i)-, *perk-, *hₐénĝhes-

Comments
Mallory J.P. and Adams D. (2006)

Other words that might be of interest
*k̂ehades- ‘hate, concern’