Doublets in Hebrew adjective and noun formation

The study examines the criteria that are responsible for competition in noun and adjective formation in Hebrew. I compare two cases where words receive an additional form with no change in meaning. I account for such changes, arguing that they target morphological and semantic transparency between related words and a morphological distinction between lexical categories. Adjectives ending with -an exhibit variation through -i suffixation (daykan~daykani ‘punctual’). This results in two competing forms that can be used interchangeably in the same semantic and syntactic contexts. I argue that such variation occurs mainly in order to avoid polycategoriality. The CaCCan pattern and the -an suffix are typical of agent nouns (saxyan ‘swimmer’) that do not undergo a change (*saxyani (as a noun)). -an ending adjectives receive additional adjectival marking in order to create a morphological distinction between the two lexical categories. This case study is compared to another case, where agent nouns and instrument nouns take an additional form, resulting in polycategoriality, as well as ambiguity. Though there seems to be a contradiction between the two criteria that trigger variation and change, I argue that the conflict can be resolved assuming a distinction between words that are derived and stored in the lexicon and words that are derived in the syntax, and that morphological processes apply in both components. The results of this study suggest that the grammar tends to tolerate polycategoriality and ambiguity when at least one of the ambiguous forms is not stored in the lexicon. In case both categories are stored in the lexicon, morphological mechanisms tend to avoid polycategoriality, and as a result, morphological change takes place. The analysis sheds light on the status of morphology in the grammar and its interaction with the lexicon and the syntax, where each interaction has its own characteristics.