Megacycle is a term that refers to one million cycles per second, commonly used in the field of electronics and telecommunications. However, there are several other synonyms that can be used to describe the same quantity. For instance, "megahertz" is a more common term, which is also used to indicate one million cycles per second. Other synonyms for megacycle include "MC/s," "mega cycles per second," and "million cycles per second." These terms are interchangeable and can be used depending on the context and preference of the user. Regardless of the synonym used, the term indicates a very high frequency, which is crucial for many technological applications in our modern world.