Simple Definition of frightful
: causing fear
: very bad or shocking
: very strong
Examples of frightful
As he fell, he let out a frightful scream.
a frightful illness that causes extreme pain
The children made a frightful mess of the kitchen.
Many critics have expressed shock at the song's frightful lyrics.
First Known Use of frightful
Seen and Heard
What made you want to look up frightful? Please tell us where you read or heard it (including the quote, if possible).