The phrase "having wavelengths of more than" refers to electromagnetic waves that have a longer wavelength than a certain threshold. Some synonyms for this phrase include "longer than," "greater than," and "beyond a certain wavelength." These phrases all convey the same meaning, indicating that the wavelengths in question are longer than a specified measure. Other synonyms might include "low-frequency" or "radio waves," which are examples of electromagnetic radiation with longer wavelengths than those visible to the human eye. Regardless of which phrase is used, the concept of electromagnetic wavelengths is essential to understanding various forms of energy, including light, heat, and sound.