While working on his hot ride, John Doe reaches for his screw driver but can't reach it. He says to Tony "Eh Tony, hand me the uh.... thingamajigger" Tony-"oh, you mean the screwdriver?" "Yeah, that's it"
So I ran over a thingamajigger on the way home from work. It's hair got caught all up in my tires. Sick.
Mrs. Robinson: "hmmm.., Luke honey can you come here? I don't understand why my thingamajiggy turned into a mirror.."
Luke: "Mom...you opened your camera in selfie mode..."
Mrs. Robinson: "Well, I don't know! You kids and these thingamajiggies...I just don't understand them!"
A word used to call something when you don't know or can't think of what to call it. examples; whotamawhatter, dohicky, watchamacallit, Hidgedinky, Dohickymajobber.