Periphrasis, the use of two independent word forms to serve the function of a single inflected word, is usually associated with verbal systems. However, it occurs also in nominal systems. Using the canonical approach to formulate the criteria for nominal periphrasis, I analyse instances of periphrasis in three Samoyedic languages (Tundra Nenets, Forest Enets and Nganasan) where it approaches the canonical ideal, and compare these to the case systems of Romanian, Armenian and Archi where the periphrasis is further away from the canonical centre. An important advantage of the canonical approach is that it provides an instrument to investigate periphrastic realisations in finer detail, and takes periphrasis as an integral part of the morphological and syntactic systems of an individual language.