[1] : The Collaborative International Dictionary of English v.0.48

whatchamacallit \whatchamacallit\, n.
   any object whose name is forgotten, or not known. also
   spelled whachamacallit.

   syn: thingumbob, doohickey, dingus, whatsis,
        what-do-you-call-it. pjc
see also:
whachamacallit 

[2] : The Collaborative International Dictionary of English v.0.48

whachamacallit \whachamacallit\, n.
   any object whose name is forgotten, or not known. also
   spelled whatchamacallit.

   syn: thingumbob, doohickey, dingus, whatsis,
        what-do-you-call-it. pjc
see also:
whatchamacallit 

[3] : WordNet (r) 2.0

whatchamacallit
     n : miscellaneous unspecified objects; "the trunk was full of
         stuff" syn: stuff, whatsis, sundry, sundries
see also:
stuff whatsis sundry sundries 

Whatchamacallit >> W Words
Whatchamacallit, definition of term: Whatchamacallit
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