-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

The Ultimate Dictionary Awaits

Expand your vocabulary and dive deeper into language with Merriam-Webster Unabridged.

1. Expanded definitions
2. Detailed etymologies
3. Advanced search tools
4. All ad-free

Discover what makes Merriam-Webster Unabridged the essential choice for true word lovers.

Start Your Free Trial Now