A "clam" is a highly unsociable creature that lacks out-going ambitions. If you have a clam in your social circle they more than likely are always the person to deny doing anything besides staying at the their
house and hanging out in their basement and smoking bongs. A typical clam
will deny being a clam and
will typically call others by their own putrid title, inorder flaunt their insecurity of their well-deserved title onto others.
"Ben, your a clam, you seriously
will never do sh*t"
Person A: "Let's go play Frisbee at the beach man!"
Person B: "Nah, i'm not leaving my
house"
Person A: "Clam...."