Doodad informal noun
Used to indicate a name of gadget or item whose true name is unknown or has been forgotten.
A: Give me that doodad to fix my car. B: Here you go.
Is this the little doodad you lost, Mark?
I'm afraid that we can't afford to buy that doodad.
A remark you make when you are leaving on the purpose of creating a stronger impact
The letter he left before leaving was his parting shot.