frightening
1. [ adjective ] causing fear or dread or terror
Synonyms: terrible dreadful awful fearful fearsome dreaded dread horrendous horrific direful dire
Examples:

"the awful war" "an awful risk" "dire news" "a career or vengeance so direful that London was shocked" "the dread presence of the headmaster" "a dreaded disease" "a dreadful storm" "a fearful howling"

Related terms: alarming
2. [ noun ] to inspire with fear
Synonyms: terrorisation terrorization
Related terms: bullying frighten
Similar spelling:   frighteningly
  frighten
  frightened
  frighten_off
  freighter
  freight_rate
  frighten_away
  freight_agent
  freightage
  freight_train
  frightfulness
  frightful
  freight_liner