The word "thingumadad" might not be a term that's officially recognized by the English language, but it's often used informally to describe an object or thing that someone can't quite remember the name of. Some possible synonyms for thingumadad include "whatchamacallit", "thingamajig", "doohickey", "gizmo", "widget", "doodad", "contraption", "apparatus", "implement", and "piece of equipment". These terms can be used to refer to anything from a technical gadget, to a household item, to an object whose name the speaker just can't quite remember. Regardless of which synonym is chosen, it serves to fill in the gap where the correct term might elude us.