The tonal system of Nuer has been a matter of much uncertainty. Here we present empirical evidence in favor of a three toneme system with some typologically rare features. One of them is an intriguing case of allotony based on the phonation of the vowel: the High toneme has a falling allotone over modal vowels. Moreover, the Rising toneme has four allotones: a rising, a mid, a low and a falling allotone. The falling allotone of the Rising toneme also occurs only on modal vowels in specific contexts. We suggest that some of the allotonic variation is motivated by tonal contour simplification. We also point out the role of free variation in some of the allotonic alternations, and the constraints that put limits on the free variation between allotones.

Here we examine newly collected Nuer data to show that Western Nilotic language Nuer distinguishes three degrees of vowel length. A minimal triplet cak ‘tick.SG.NOM” ~ ca:k “milk.PL.NOM” ~ ca::k “milk.PL.GEN” provides an example of this contrast.  Since vowel length plays a crucial role in nominal inflection, we examine distribution of the three degrees of vowel length in the nominal paradigm.  Our preliminary conclusion is that Nuer vowels are lexically specified for two degrees of vowel length only – short and long, and that overlong vowels emerge only as an outcome of a morphological operation which lengthens short and long vowels.   Since we conclude that the three degrees of vowel length do not have equal status in the Nuer grammar, our findings therefore are in line with the reported typological markedness of the three-way contrast in vowel length.

It is not uncommon for inflected nominal forms to be incorporated into verbal paradigms, as in Imonda progressive construction tōbtō soh-ia ale-f 'he is looking for fish (lit. fish search-LOC stay-PRS)', where the verbal noun 'search' is in the locative case. Equally, nominal inflection classes are not uncommon. But the two rarely cooccur. We present two case studies (the only examples we are aware of) as a contribution to the typology of inflection class systems: the Western Nilotic language Nuer, and Old Irish. In these languages nominal inflection class distinctions in case marking have become part of the verbal paradigm through the incorporation of constructions involving deverbal nouns. This provides a unique context for observing the properties of inflection classes. In Nuer, case inflection of the verbal noun can be deduced through a cascading series of implicatures, laying bare processes which are entirely covert in the ordinary noun system. With Old Irish, its transition to the modern period was accompanied by a split in the behaviour of verbal nouns, whose inflection class system was simplified when used verbally, but left intact in other contexts, showing that incorporation into the verbal paradigm had real effects on the system.

Nouns in Nuer (Western Nilotic) have been presented as an extreme example of inflectional complexity, where a 'chaotic' distribution of suffixes combines with dozens of different stem modifications to yield dozens of inflection classes (Frank 1999, Baerman 2012. We show that all of the apparent surface variety can be reduced to a handful of operations. The proliferation of inflection classes is due to a property we call paradigmatic saturation: practically every combination of inflectional operations is attested, yielding the maximum variety with the minimum of means.*

Tone is indispensable for understanding many morphological systems of the world. Tonal phenomena may serve the morphological needs of a language in a variety of ways: segmental affixes may be specified for tone just like roots are; affixes may have purely tonal exponents that associate to segmental material provided by other morphemes; affixes may consist of tonal melodies, or “templates”; and tonal processes may apply in a way that is sensitive to morphosyntactic boundaries, delineating word-internal structure. Two behaviors set tonal morphemes apart from other kinds of affixes: their mobility and their ability to apply phrasally (i.e., beyond the limits of the word). Both floating tones and tonal templates can apply to words that are either phonologically grouped with the word containing the tonal morpheme or syntactically dependent on it. Problems generally associated with featural morphology are even more acute in regard to tonal morphology because of the vast diversity of tonal phenomena and the versatility with which the human language faculty puts pitch to use. The ambiguity associated with assigning a proper role to tone in a given morphological system necessitates placing further constraints on our theory of grammar. Perhaps more than any other morphological phenomena, grammatical tone exposes an inadequacy in our understanding both of the relationship between phonological and morphological modules of grammar and of the way that phonology may reference morphological information.