A compound in which a metal atom or ion is bound to an organic group. Organometallic compounds may have single metal–carbon bonds, as in the aluminium alkyls (e.g. Al(CH3)3). In some cases, the bonding is to the pi electrons of a double bond, as in complexes formed between platinum and ethene, or to the pi electrons of a ring, as in ferrocene. The theoretical analysis of organometallic compounds is facilitated by electron counting rules and the isolobal principle.
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