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)

• lightning-tube
• lightning-tubes
• light of nature
• light-o'-love
• light-o'-loves
• light opera
• light-organ
• light-organs
• light out
• light pen
• light pens
• light pollution
• light-proof
• light railway
• light railways
• lights
• lightship
• lightships
• light show
• light shows
• lightsome
• lightsomely
• lightsomeness
• lightsomenesses
• lights out