aryl groups

https://doi.org/10.1351/goldbook.A00464
Groups derived from arenes by removal of a hydrogen atom from a ring carbon atom. Groups similarly derived from heteroarenes are sometimes subsumed in this definition. E.g. o-tolyl:
A00464.png
See: arenes, heteroarenes, heteroaryl groups
Source:
PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1320 (https://doi.org/10.1351/pac199567081307)