Go to 'thermo-' entry Go to 'dino-' entry Go to 'chondro-' entry Go to 'aero-' entry Go to '-logy' entry Go to 'thaumato-' entry Go to 'nano-' entry Go to '-sophy' entry Go to 'bucco-' entry Go to '-ism' entry Go to '-lysis' entry Go to 'galacto-' entry Go to '-anthropy' entry Go to 'pneumo-' entry Go to '-ploitation' entry Go to '-lithic' entry Go to '-sepalous' entry Go to 'onco-' entry Go to '-parous' entry Go to 'dermato-' entry Go to 'multi-' entry Go to 'dodeca-' entry Go to '-zoon' entry Go to 'vermi-' entry Go to 'crystallo-' entry Go to 'biblio-' entry Go to 'eco-' entry Go to 'juxta-' entry Go to 'facio-' entry
Affixes: the building blocks of English
Affixes: the building blocks of English

-yl Also -oyl.

Forming names of chemical radicals.

[Greek hulē, material, matter.]

Examples include acetyl, the radical CH3CO- derived from acetic acid; benzyl, the C6H5CH2- group from toluene; carbonyl, the CO- group; ethyl, the C2H5- group from ethane; hydroxyl, the -OH group; methyl, the CH3- group from methane; and phenyl, the C6H5- group from benzene.

The ending -oyl forms the names of acid radicals from associated carboxylic acids, whose names end in -oic: benzoyl from benzoic acid, caproyl from caproic acid, pantoyl from pantanoic acid.

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