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from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. the bicyclic hydrocarbon formed from two cyclopentadiene rings linked with a double bond; any derivative of this compound
  • n. any heterocyclic analogue of these compounds


Sorry, no etymologies found.


  • One of the best examples in recent years, tetracarbonly-diruthenium fulvalene, requires the use of ruthenium, which is rare and expensive.

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