'Frightening' definitions:

Definition of 'frightening'

From: WordNet
adjective
Causing fear or dread or terror; "the awful war"; "an awful risk"; "dire news"; "a career or vengeance so direful that London was shocked"; "the dread presence of the headmaster"; "polio is no longer the dreaded disease it once was"; "a dreadful storm"; "a fearful howling"; "horrendous explosions shook the city"; "a terrible curse" [syn: awful, dire, direful, dread(a), dreaded, dreadful, fearful, fearsome, frightening, horrendous, horrific, terrible]
noun
The act of inspiring with fear [syn: terrorization, terrorisation, frightening]

Definition of 'Frightening'

From: GCIDE
  • Frighten \Fright"en\, v. t. [imp. Frightened; p. pr. & vb. n. Frightening.] [See Fright, v. t.] To disturb with fear; to throw into a state of alarm or fright; to affright; to terrify. [1913 Webster]
  • More frightened than hurt. --Old Proverb. [1913 Webster]