The key difference between dikaryotic and diploid is that dikaryotic cell is the cell that contains two genetically distinct nuclei while diploid cell is a cell that contains two sets of chromosomes.
Generally, a cell contains only one nucleus. However, in some instances, cells contain more than one nucleus. In sexual reproduction, we can also observe cells with two nuclei. Dikaryon or dikaryotic cell is a cell at the stage of having two nuclei, especially seen in fungi. However, it is the moment which is prior to the karyogamy or nuclear fusion. When the karyogamy occurs, dikaryon transforms into a diploid cell, which is a cell that contains two sets of chromosomes.
