-oyl

noun combining form

-o·​yl

əwəl,

ə(ˌ)wil,

əˌwēl

plural -s

: acid radical

—used in the system of nomenclature adopted by the International Union of Pure and Applied Chemistry in names of radicals derived from acids whose names end in -oic

decanoyl

and also most other organic acids

oleoyl

phthaloyl

compare -yl

Word History

Etymology

International Scientific Vocabulary -o- (as in -oic) + -yl

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