The act of mixing or blending things together; a technical or formal term for combination or mixture.
From Latin admiscere (ad- 'to' + miscere 'to mix') plus -tion, a suffix creating nouns from verbs. The -tion suffix, from Latin -tio, is one of the most productive noun-forming suffixes in English.
Admixtion is another rarity—it's to admix as creation is to create. English prefers 'admixture' for the noun form, but admixtion appears occasionally in very formal or technical writing, showing how Latin-based suffixes can stack.
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