Illustrated Glossary of Organic Chemistry

Kekule structure: A Lewis structure in which bonded electron pairs in covalent bonds are shown as lines. The most famous Kekule structures are what we would now call the two most significant resonance contributors of benzene. A Kekule structure should not include lone pairs or formal charges, because the electron was not discovered until well after Kekule starting using this notation. Adding lone pairs converts a Kekule structure into a Lewis structure.

The Kekule structures for benzene

A typical Kekule structure. Does not include lone pairs.		Corresponding Lewis structure. Lone pairs shown.