The scenario of constant-roll inflation in the framework of a noncanonical inflaton model is studied. Both of these modifications lead to the appearance of some differences in the slow-roll parameters besides the Friedmann equations, resulting in a better justification of theoretical predictions compared to observations. Phenomenologically, by assuming a constant η, i.e., a second slow-roll parameter, and recalculating the related perturbation equations, obviously there should appear some modification in the scalar spectral index and amplitude of scalar perturbations. It is shown that finding an exact solution for the Hubble parameter is one of the main advantages and triumphs of this approach. Also, whereas making a connection between subhorizon and super-horizon regions has a crucial role in inflationary studies, the main perturbation parameters are obtained at the horizon crossing time. To examine the accuracy of our results, we consider the Planck 2018 results as a confident criterion. To do so by virtue of the r−ns diagram, the acceptable ranges of the free parameters of the model are illustrated. As a result, it is found that the second slow-roll parameter should be a positive constant and smaller than unity. By constraining the free parameters of the model, also, an energy scale of inflation is estimated that is of order 10−2. Even more, by investigating the attractor behavior of the model, it is clear that the aforementioned properties can be appropriately satisfied.
