4th Grade Science Vocabulary Words: Sound and Light

Updated August 12, 2021
4th Grade Science Vocabulary Words: Sound and Light
    4th Grade Science Vocabulary Words: Sound and Light
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Sound and light are essential parts of our world, and they are also important when studying science. Fourth graders can review vocabulary words that describe how sound and light travel and how we measure them. Keep reading for some 4th grade science vocabulary words and definitions for sound and light lessons, followed by a few online resources and a practice quiz.

Sound Vocabulary Words

Did you hear that? The study of sound involves measuring sound waves and how the ear interprets those waves as sound energy. Some important sound vocabulary words include:

  • absorption – when sound energy hits an object and is converted into another form of energy; the opposite of reflection
  • acoustics – the characteristics of a space that control how sound waves move
  • ambiance – the resting sound of an area
  • amplifier – device that increases an electric current to increase volume
  • amplitude – the measure that a sound wave travels from its resting place
  • decibel – unit of measurement to indicate the volume of a sound
  • echo – a reflection of sound
  • frequency – measurement of the number of times a sound wave repeats
  • hertz – unit to measure frequency
  • loudness – magnitude of of sound
  • medium – substance (gas, liquid or solid) through which sound waves travel
  • pitch – how high or low a sound is; determined by the frequency of the vibration
  • resonance – reflection that prolongs the sound
  • sonic boom – a shock wave that consists of compressed sound waves created when something moves faster than the speed of sound
  • sound energy – energy produced by the vibration of sound waves
  • sound wave – sound travels in a wave, which is a moving pattern of high and low pressure or vibrations
  • speed of sound – how fast sound moves through an object
  • vibrate – to move back and forth
  • volume – how much sound energy reaches the ear
  • wavelength – the length between the compressions in a sound wave
  • wave speed – distance that a sound wave travels without becoming absorbed

Light Vocabulary Words

Like sound, light moves in waves. But unlike sound, which is interpreted by our sense of hearing, light energy (or radiant energy) is interpreted by our sense of sight. You may find that some words are repeated from the sound section but have different definitions that relate to light.

Scientific words for light include:

  • absorption – absorption happens when light stops as it hits an opaque object; the opposite of reflection
  • beam – stream of light pointed in one direction
  • concave – a curved lens like the inside of a sphere
  • convex lens – a curved lens like the outside of a sphere
  • diffraction – how light bends as it passes around an object
  • electromagnetic wave – type of wave that includes both electric and magnetic energy
  • infrared – radiant energy that is not visible but can be felt as heat (or thermal energy)
  • laser – acronym for Light Amplification by the Stimulated Emission of Radiation; beam of very concentrated light that emits radiation
  • opaquean object is opaque when all light is absorbed or reflected; no image can be seen
  • photon – particle that carries visible light and other forms of electromagnetic radiation
  • prism – something that bends light, but is not a lens
  • radiant energy – the energy produced by electromagnetic waves; also known as light energy
  • rainbow – arch in the sky formed by the refraction of sunlight through raindrops
  • reflection – when light bounces off of an object
  • refraction – when light is bent as it moves through one kind of matter to another
  • shadow – shape produced by light being blocked by an opaque object
  • translucent – a substance that allows some light to pass through it
  • transparent – a substance that allows most of the light to pass through it
  • visible spectrum – the light energy that humans can see

Science Vocabulary Quiz

If you’d like some extra practice, try out a quiz on 4th grade science vocabulary words for sound and light. It covers the terms listed in this article.

A. Directions: Decide whether each statement is true or false. Use the definitions above if you need help.

  1. Light is electromagnetic radiation.
  2. Opaque objects can either absorb or reflect light.
  3. Transparent substances reflect light.
  4. A convex lens is curved outwards.
  5. A prism is a type of lens
  6. You can see your reflection on an opaque object
  7. The visible spectrum is light you can see.
  8. All light passes through translucent objects.
  9. A concave lens is like the inside of a sphere.
  10. Refraction means the light stops.

B. Directions: Decide which sound vocabulary word (amplitude, sonic boom, pitch, echo, sound, sound wave, speed of sound, vibrate, volume, wavelength) is defined in each statement below.

  1. repeated vibrations that you can hear
  2. how a sound wave is measured
  3. moving pattern of high and low pressure
  4. distance between compressions in a sound wave
  5. move back and forth
  6. sound reflection
  7. how high or low a sound is
  8. the amount of sound energy that reaches your ear
  9. how fast sound moves through something
  10. compressed sound waves made when an object goes faster than the speed of sound


How did you do? Check out the answers for both exercises here.


  1. T
  2. T
  3. F
  4. T
  5. F
  6. F
  7. T
  8. F
  9. T
  10. F


  1. sound
  2. amplitude
  3. sound wave
  4. wave length
  5. vibrate
  6. echo
  7. pitch
  8. volume
  9. speed of sound
  10. sonic boom

Online Resources

If you need more science vocabulary resources, these are some good options for teachers and students:

More Elementary Science Vocabulary

Building a foundation of scientific terms is a great way to introduce young students to the world of science. They can use these terms to understand more about the world around them. Check out a further list of general science terms made simple for kids.