Inward and Outward Allomorph Selection

Abstract

AbstractThis entry provides an overview of directionality relations in allomorphy selection. One type is ‘inward conditioning’, where the trigger is in a structurally outer position compared to the target of allomorphy (i.e. it is further away from the lexical head of the construction). This type can also be referred to as ‘outward sensitivity’. Its counterpart is ‘outward conditioning’, where it is the trigger which is in an inner position and the target in an outer position (it can also be referred to as ‘inward sensitivity’). A number of typologically diverse cases are presented to illustrate directional asymmetries in allomorphy selection. One robust generalization involves ‘grammatically conditioned allomorphy’, in which the trigger is a morphosyntactic feature (e.g. [plural]), feature bundle (e.g. [3.sg.fem]), or category (e.g. [tense]). In this type of allomorphy, both inward conditioning and outward conditioning are widespread, showing a clear directional symmetry. In contrast, other types of allomorphy such as ‘lexically conditioned’ (the trigger is a particular lexical root), ‘morphologically conditioned’ (a purely morphological feature, e.g. conjugation class) and ‘phonologically conditioned allomorphy’ show a clear directional asymmetry. Here, allomorph selection almost always involves outward conditioning, in other words, the trigger is in an inner position. Cases of inward conditioning are rare and controversial. Taken all together, the propensity for triggers to be inward compared to targets is called the ‘directional asymmetry in allomorphy selection’.