the act of inspiring with fear
"The sudden thunderclap was frightening to the small dog, who immediately curled up under the bed."
present participle of frighten
"The frightening sound echoing through the hallway made everyone jump in surprise."
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"
Causing fear; of capable of causing fear; scary.
"The thunderstorm was frightening, sending everyone inside before the first bolt of lightning struck."