Reconciling underspecification with the overlapping decomposition

Natural language grammar contains pockets of linear morphological contiguity, in which formal identity between non-contiguous categories is either unattested or extremely rare. Also called *ABA domains, the analysis of these etiologically heterogeneous patterns has been a fruitful site of cross-theoretic discourse. Following Caha (2017), surface *ABA distributions may be classified as resulting from one of at least two morphosyntactic decompositions: cumulating and overlapping. The cumulating decomposition characterizes Bobaljik's (2012) comparative suppletion, and describes domains in which the final category of an *ABA domain is the most featurally or representationally complex. In contrast, the overlapping decomposition describes domains in which the medial category is the most complex, which Caha further argues is poorly handled by realizational architectures that assume underspecification. This study reconciles underspecification with the overlapping distribution by means of a requirement of contextual contiguity, in which a Vocabulary entry can only realize a complex feature bundle [X, Y] if and only if there exists another entry that realizes either of the simplex features [X] or [Y].