The linear canonical transform (LCT) has been successfully applied in some fields, including signal processing and optics. Some authors based on the linear canonical transform, proposed the quaternionic linear canonical transform (QLCT). In this paper, first, we propose the right-sided quaternion windowed linear canonical transform (RQWLCT). Next, using the spectral representation of the QLCT, we derive several important properties of the RQWLCT such as bounded, shift, orthogonality relation. Finally, Using the properties of the RQWLCT we establish an uncertainty principle for the RQWLCT. This uncertainty principle prescribes a lower bound on the product of the effective widths of quaternion-valued signals in the spatial and frequency domains. It is shown that only a 2D Gaussian signal minimizes the uncertainty. This uncertainty principle gives information how a complex function and its RQWLCT relate.