Hair-raising is typically used to describe something that's intensely frightening or thrilling. There are numerous synonyms for the word hair-raising, including spine-tingling, unnerving, chilling, blood-curdling, frightening, and terrifying. These words are all excellent alternatives to hair-raising, depending on the context in which they are being used.
For example, spine-tingling might be the best choice to describe a paranormal experience, while unnerving might be more appropriate for an unexpected encounter with a wild animal. Blood-curdling is frequently associated with horror movies, while terrifying could be used to describe a traumatic event that leaves a lasting impact.
No matter which synonym you choose, using descriptive language can make a story or experience more memorable and impactful.