がらっと
Meanings
Adverb
1. (opening) with a clatter; loudly; flinging (open) (Onomatopoeia)
2. (changing) completely; dramatically; suddenly (Onomatopoeia)
Other readings
Examples1
僕
Once I arrived home from school, I heard some sounds coming from my closet, and thinking that it was just our pet cat Chiro, I opened the door wide open, and instead found some guy I didn't know inside.