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The magnitude of the polar-vector Cabibbo angle ${\ensuremath{\theta}}_{V}$ obtained from ${K}_{e3}$ decay has been reevaluated using the Kemmer description of pseudoscalar mesons. We find ${{\ensuremath{\theta}}_{V}}^{(\mathrm{K})}={0.192}_{+}\ifmmode\pm\else\textpm\fi{}0.016$. This compares favorably with the value ${{\ensuremath{\theta}}_{V}}^{\ensuremath{\beta}}={0.188}_{\ensuremath{-}}\ifmmode\pm\else\textpm\fi{}0.007$ obtained for ${0}^{+}\ensuremath{\rightarrow}{0}^{+}\ensuremath{\beta}$ decays, and thus removes the discrepancy between ${{\ensuremath{\theta}}_{V}}^{(\ensuremath{\beta})}$ and the value obtained from the conventional Klein-Gordon ${K}_{e3}$ description, ${{\ensuremath{\theta}}_{V}}^{(\mathrm{K}\ensuremath{-}\mathrm{G})}={0.235}_{\ensuremath{-}}\ifmmode\pm\else\textpm\fi{}0.019$. Combining the Kemmer and the $\ensuremath{\beta}$-decay results leads to a "best" value of ${\ensuremath{\theta}}_{V}={0.188}_{+}\ifmmode\pm\else\textpm\fi{}0.006$. A new determination of the axial-vector Cabibbo angles ${{\ensuremath{\theta}}_{A}}^{(\mathrm{K})}$ and ${{\ensuremath{\theta}}_{A}}^{(\mathrm{K}\ensuremath{-}\mathrm{G})}$ is also obtained.