Other forms: thingies
Any item — usually a small object — whose name you can't remember (or just don't know) can be called a thingy. Obviously, it's some sort of thing, but adding a -y is almost like giving it a friendly nickname.
The word thingy sounds cutesy, but it's a useful word when you're stuck. Don't know the name of that tool in the drawer, but you need it to get the last olive out of the skinny jar? Ask me if I'll hand you the thingy with the blue handle. Chances are I'll look in the drawer and see what you mean! Thingies often need a little description. If I ask for one of those stretchy thingies used to make a ponytail, would you understand?