In some Norwegian dialects, such as older Oslo dialect, the noun mamma ‘mother’ unexpectedly appears to be masculine. The Nordreisa dialect (Northern Norwegian) goes one step further. The word looks like it is masculine, but only in the definite form. This is an unusual “split” because gender mixture is normally based on number, not definiteness (but we find some few corroborative examples in other Norwegian dialects and different, but converging evidence on the Web). The Nordreisa example of mamma is unusual also because agreement targets are affected differently. The preference is for masculine agreement within the noun phrase, but for feminine agreement outside it. This is, therefore, an intriguing example since it combines a split based on definiteness with different gender requirements according to different agreement targets. On careful analysis, and given strict adherence to the classical, agreement-based definition of gender, the unusual behavior of mamma turns out to conform to the Agreement Hierarchy.