What term describes the distance from crest to crest in a wave?

The term that describes the distance from crest to crest in a wave is wavelength. Wavelength is a key characteristic of waves, representing the physical distance between two consecutive peaks (crests) in a wave's pattern. This measurement is crucial in understanding various properties of waves, including their behavior and interactions with other waves.

Other terms in the context of waves refer to different characteristics: amplitude refers to the height of the wave from its rest position to its crest or trough, frequency indicates how often a wave repeats itself over a given period, and crest specifically refers to the highest point of a wave. Thus, the definition of wavelength distinctly focuses on the spatial measurement relevant to the distance between crests, making it the correct choice.