What is the term used to describe a distribution with one prominent peak?

The term used to describe a distribution with one prominent peak is "unimodal." In statistical terminology, a unimodal distribution indicates that the data clusters around a single value, resulting in a peak that is the highest point in the distribution.

This contrasts with other types of distributions: a bimodal distribution has two distinct peaks, indicating the presence of two modes or frequent values; a multimodal distribution features multiple peaks, suggesting that the data has several modes; and a trimodal distribution specifically refers to a case with three significant peaks. By understanding these distinctions, it becomes clear why "unimodal" is the appropriate term for a distribution characterized by a single prominent peak.