grisly /ˈɡɹɪzli/adjective 1adverb 1forms 5 adjective1 •Horrifyingly repellent; gruesome, terrifying.The photographs of the killings depict a grisly scene. adverb1 •(no longer used) In a horrible or terrible manner; in a terrifying way. formsgrislies · grislier · more grisly · grisliest · most grisly