Thingamajig
Definition 1 of 2

Context
Use this word when you're unsure of an object's name

I need that thingamajig, what's it called again?
Casual
Best used in informal settings

This conversation is quite casual so using 'thingamajig' fits nicely.
Easier Communication
Helps simplify discussions about items people might not recognize outright

If you forget the name of a toy, calling it a 'thingamajig' works.
Compare with
doohickeygadgetwidgetgizmo
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