Within WORD-BASED, PARADIGM-BASED or ABSTRACTIVE models of inflectional systems, only full inflected wordforms are considered primitives; subword strings are treated not as distinct entities, but as abstract generalisations inferred by speakers across multiple inflected forms. These models stand in contrast to CONSTRUCTIVE and MORPHEME-BASED approaches, which proceed from individual, distinct subword units to full words. An argument consistently adduced in favour of abstractive approaches is that they afford a descriptive advantage regarding FUSIONAL systems characterised by pervasive non-canonical exponence. Such exponence includes MORPHOMIC structure, i.e. inflectional distributions which are systematic, recurrent, and irreducibly morphological. Three types of morphomes are currently recognised: inflectional classes or RHIZOMORPHOMES; paradigmatic distribution patterns or METAMORPHOMES; and patterns of realisation or MEROMORPHOMES. Rhizomorphomes and metamorphomes are known to be widespread within fusional systems, whereas meromorphomes have thus far been described only in an AGGLUTINATING system. Rhizomorphomes and metamorphomes have been extensively studied for Romance, and typical features of their synchronic and diachronic behaviour are exemplified by data from verb conjugation in French and Occitan (Gallo-Romance). However, incidence of these structures is not confined to fusional systems. Exploration of synthetic verb forms in standard Swahili (North-East Coast Bantu), a popularly cited exemplar of agglutinating inflection, reveals the presence of rhizomorphomes and metamorphomes as well as other instances of non-canonical exponence: for this language, too, abstractive and paradigmatic approaches afford a descriptive advantage. While research on meromorphomes remains at an earlier stage, key typological parameters of inflectional systems liable to exhibit meromorphomes can nevertheless be identified. These parameters suggest the potential presence of meromorphomes in the periphery of fusional systems as well as in agglutinating systems.