| No. | Term | Definition |
|---|---|---|
| 1. | afterglow | Faint light lingering after sunset. |
| 2. | arc flash | Sudden bright electrical discharge. |
| 3. | aurora | Polar sky glow from solar particles. |
| 4. | backlight | Light shining from behind a subject. |
| 5. | beam | Narrow stream of light. |
| 6. | bioluminescence | Light produced by living organisms. |
| 7. | blackout | Complete loss of electric lighting. |
| 8. | blaze | Very bright, intense firelight. |
| 9. | blink | Brief flash or closing of eyes. |
| 10. | bolt | Sudden discharge of lightning. |
| 11. | brilliance | Exceptional brightness or radiance. |
| 12. | candlelight | Soft light from a candle flame. |
| 13. | chromatic | Relating to color in light. |
| 14. | circuit | Path for electric current flow. |
| 15. | cloud-to-ground | Lightning striking from cloud to earth. |
| 16. | corona | Glowing halo around a light source. |
| 17. | daylight | Natural light from the sun. |
| 18. | dazzle | Overwhelm vision with bright light. |
| 19. | diffraction | Light bending around edges. |
| 20. | diffuse | Spread out; not concentrated light. |
| 21. | dimmer | Device reducing light intensity. |
| 22. | diode | One-way device; used in LEDs. |
| 23. | discharge | Release of electricity through air. |
| 24. | electricity | Energy from moving electric charges. |
| 25. | electroluminescence | Light emitted by electric current. |
| 26. | electromagnetic | Relating to electric and magnetic fields. |
| 27. | electron | Negatively charged subatomic particle. |
| 28. | energy | Capacity to do work; power source. |
| 29. | exposure | Amount of light reaching sensor/film. |
| 30. | filament | Thin wire that glows when heated. |
| 31. | firefly | Insect producing bioluminescent light. |
| 32. | flash | Sudden brief burst of light. |
| 33. | flicker | Unsteady, wavering light. |
| 34. | fluorescence | Glow from absorbing and re-emitting light. |
| 35. | focal point | Point where light rays converge. |
| 36. | gamma ray | Highest-energy electromagnetic radiation. |
| 37. | glare | Harsh, uncomfortable brightness. |
| 38. | glimmer | Faint, unsteady light. |
| 39. | glint | Small, quick flash of light. |
| 40. | glow | Steady light without flame. |
| 41. | gradient | Gradual change in brightness or color. |
| 42. | halation | Halo effect around bright areas. |
| 43. | halo | Ring of light around a source. |
| 44. | headlamp | Lamp worn on the head. |
| 45. | high voltage | Large electrical potential difference. |
| 46. | horizon glow | Light seen near the horizon. |
| 47. | illumination | Light provided to brighten an area. |
| 48. | incandescence | Light from heat. |
| 49. | infrared | Radiation just beyond visible red. |
| 50. | insulator | Material resisting electric current flow. |
| 51. | ion | Atom or molecule with charge. |
| 52. | ionization | Creation of ions from atoms. |
| 53. | joule | Unit of energy. |
| 54. | kWh | Energy unit: kilowatt-hour. |
| 55. | lamp | Device that produces light. |
| 56. | laser | Focused coherent light beam. |
| 57. | lens | Curved glass focusing light. |
| 58. | lightning | Atmospheric electrical discharge. |
| 59. | lightning rod | Conductor directing lightning safely to ground. |
| 60. | lumen | Unit of visible light output. |
| 61. | luminance | Brightness of a surface. |
| 62. | luminescence | Light emission without heat. |
| 63. | magnesium flare | Brilliant white light from burning magnesium. |
| 64. | moonlight | Sunlight reflected by the moon. |
| 65. | neon | Gas used in bright signs. |
| 66. | neon glow | Colored light from neon discharge. |
| 67. | nightlight | Small lamp for dim illumination. |
| 68. | optics | Study of light and vision. |
| 69. | overexpose | Make image too bright with excess light. |
| 70. | phosphorescence | Glow that persists after excitation. |
| 71. | photon | Particle of light. |
| 72. | plasma | Ionized gas in lightning channels. |
| 73. | polarization | Orientation of light wave oscillations. |
| 74. | prism | Transparent object splitting light colors. |
| 75. | radiance | Bright, glowing appearance. |
| 76. | radiation | Energy emitted as waves or particles. |
| 77. | rainbow | Spectrum arc from refracted sunlight. |
| 78. | ray | Line representing direction of light. |
| 79. | reflection | Light bouncing off a surface. |
| 80. | refraction | Light bending entering a new medium. |
| 81. | resistance | Opposition to electric current. |
| 82. | resistor | Component limiting electric current. |
| 83. | scintillation | Rapid sparkling or twinkling. |
| 84. | searchlight | Powerful directional beam lamp. |
| 85. | shadow | Dark area where light is blocked. |
| 86. | shimmer | Soft, wavering reflected light. |
| 87. | shine | Emit or reflect light brightly. |
| 88. | spark | Small fiery electrical flash. |
| 89. | spectrum | Range of light wavelengths. |
| 90. | strobe | Rapid flashing light. |
| 91. | sunbeam | Beam of sunlight. |
| 92. | sunlight | Light from the sun. |
| 93. | surge | Sudden increase in electrical power. |
| 94. | thunder | Sound produced by lightning heating air. |
| 95. | thunderbolt | Lightning flash, especially striking. |
| 96. | torch | Portable light; flashlight or flame. |
| 97. | translucent | Lets light through, not clearly. |
| 98. | ultraviolet | Radiation beyond visible violet. |
| 99. | underexpose | Make image too dark with too little light. |
| 100. | voltage | Electrical potential difference. |