Vulnerable spot is a term used to describe a weak point or area of vulnerability. A blindside is a nine letter term that refers to an unexpected attack or disadvantage. An underbelly is a ten letter term that refers to the vulnerable underside of an animal or person. An Achilles heel is a twelve letter term that refers to a weakness in spite of overall strength. Finally, a chink in the armor is a fifteen letter term that refers to a weakness in an otherwise strong defense. All of these terms are used to describe a vulnerable spot.