thingamajig
noun

- a small article the actual name of which one either does not know or cannot remember
- something that is hard to classify or whose name is unknown or forgotten

Merriam-Webster

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ORIGIN

According to The Shorter Oxford Dictionary “Thingamajig” is of early 19th century origin and evolved from Thingummy (late 18th century) which evolved from Thingum (late 17th Century) which evolved from Thing (Old English 6-9th Century), and is related to Old High German (ding) and Old Frisian (thing), both with origins in Norse.

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SYNONYMS

dingus, doodad, doohickey, hickey, thingamabob, thingummy, thingie (thingy) whatchamacallit, whatnot, whatsit (wotsit), wotsisname, wotsername

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USAGES

These are very useful terms for when we are lost for words. Whether no vocabulary exists, or whether we have momentarily forgotten a word:

- Where did I put that thingamajig? (that thing whose name I forgot)
- How did he like the whatchamercallit? (what would you call it)
- The thingie is in the cupboard (the thing)
- What have you done with the wotsit? (what is it)
- Have you seen wotsisname? (what is his name?)
- Where is wotsername? (what is her name?)

Best of all are tricks for pointing to words do not want to say:

- I must do “you know what”
- I have a meeting with “you know who”

Oh, and I just remembered the best one for ending any conversation:

- Must stop now, I have to go you know where!