1. Relating to or characteristic of the classical Greek civilization
   - Hellenic, Hellenistic

See also: Hellenism

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• order Gnetales
• order Graminales
• order Gregarinida
• order Gruiformes
• order Guttiferales
• order Gymnophiona
• order Haemosporidia
• order Haplosporidia
• order Heliozoa
• order Helotiales
• order Hemiptera
• order Heterosomata
• order Heterotrichales
• order Hymenogastrales
• order Hymenoptera
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• order Hyracoidea
• order Ichthyosauria
• order Ictodosauria
• order Insectivora
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• order Isoetales