Definition of tertium quid
1 : a middle course or an intermediate component <where there are two systems of law and two orders of courts, there must…be some tertium quid to deal with conflicts of law and jurisdiction — Ernest Baker>
2 : a third party of ambiguous status <there was a man and his wife and a tertium quid — Rudyard Kipling>
Origin and Etymology of tertium quid
Late Latin, literally, third something; from its failing to fit into a dichotomy
First Known Use: circa 1724
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