precursor /prē-kûrˈsər/

1. Something that exists or goes in advance of another
2. An indication of the approach of an event
3. A forerunner, herald or harbinger
4. A predecessor
5. A substance from which the one in question is derived or manufactured (chem)

precurˈsive or precurˈsory adjective

• heptagons
• Heptagynia
• heptagynous
• heptahedra
• heptahedron
• heptahedrons
• Heptameron
• heptamerous
• heptameter
• heptameters
• Heptandria
• heptandrous
• heptane
• heptanes
• heptapodic
• heptapodies
• heptapody
• heptarch
• heptarchic
• heptarchies
• heptarchist
• heptarchists
• heptarchs
• heptarchy
• heptasyllabic