Cosinusoidal describes a mathematical function that oscillates with a cosine wave. There are several synonyms for this word, including sinusoidal, cosine-like, sine-like, and periodic. Sinusoidal, like cosinusoidal, refers to a function that follows a sine wave pattern, while cosine-like and sine-like describe a function that resembles a cosine or sine wave, respectively. Periodic is a broader term that refers to any function that repeats itself after a certain interval, including cosinusoidal functions. These synonyms are useful in both mathematics and physics to describe various waves and oscillations, such as sound and light waves.