thing‧a‧ma‧jig /ˈθɪŋəmədʒɪɡ, ˈθɪŋəmɪdʒɪɡ/ (also thing‧a‧ma-bob /ˈθɪŋəməbɒb, ˈθɪŋəmɪbɒb $ -bɑːb/ thing‧y /ˈθɪŋi/) noun [countable] spoken
[Date: 1800-1900; Origin: thingum 'thingamajig' (17-19 centuries), from thing]

1. used when you cannot remember or do not know the name of the thing you want to mention:
What do you call that thingamajig? You know – the circle with the line through it.

2. British English used when you cannot remember or do not know the name of the person you want to mention:
Is thingy going?

[TahlilGaran] Dictionary of Contemporary English ▲