Univalent groups containing carbon, which are thus organic, but which have their free valence at an atom other than carbon. This collective term is seldom used; specific subclasses are more frequently encountered (organothio or organylthio, organogermanium or organylgermanium groups). The synonymous term organoelement groups is occasionally encountered. E.g. phenoxy, acetamido, pyridinio ($\ce{C5H5N^{+}}$), thiocyanato ($\ce{N#C–S−}$), trimethylsilyl; but not hydroxyphenyl, aminoacetyl.