This study presents the cosine Kumaraswamy family of distributions, a new family of prob-ability distributions formed by combining the cosine and Kumaraswamy families. Several statistical properties of the family are derived, such as the quantile function, moments, mo-ment-generating function, survival and hazard functions, and order statistics. The model parameters are estimated using the maximum likelihood method. A special case, called the cosine Kumaraswamy Lomax distribution, is discussed in detail, and its probability density and hazard functions are explored for different parameter values. To assess its usefulness, the cosine Kumaraswamy Lomax distribution is compared with other well-known models using three real datasets from the medical and engineering fields. The findings show that this dis-tribution provides a better fit than the competing models, proving its flexibility and suitability for different types of data. Overall, the cosine Kumaraswamy family offers a useful addition to statistical modeling with strong practical applications.