Where does “noon thing” come from?

noon thing (Middle English) comes from Old English nāþing.

Ancestry of “noon thing”, step by step

noon thing traces back through two separate lines of ancestry.

via Old English nāþing

StepLanguageWordMeaning
1Old Englishnāþing

via Old English nān þing

StepLanguageWordMeaning
1Old Englishnān þingnothing
Every word from Old English nāþing