This dissertation investigates comparative morphology in Ukrainian adjectives, adverbs, and deadjectival verbs. The comparative suffix in Ukrainian has two allomorphs: -š, as in molod-š-yj ‘younger’, and -iš, as in vesel-iš-yj ‘merrier’. I claim that the allomorph -iš is in fact comprised of two morphemes, -i and -š. I account for the comparative allomorphy in terms of root sizes using Nanosyntax. Big roots like molod take only one comparative morpheme, while smaller roots like vesel take both comparative morphemes. These are simple adjectives, which consist of the root, the comparative morpeme(s) and the agreement marker. There are also complex adjectives, which have an additional morpheme following the root. Considering both simple and complex adjectives, the main theoretical proposal of this dissertation is that Ukrainian adjectives come in seven different root sizes (and shapes), corresponding to seven different empirical patterns. The size of the root depends on the amount of morphology present in the comparative: the less morphology a comparative adjective takes, the bigger its root is. These seven adjectival root sizes derive both adverbs and deadjectival verbs. Ukrainian deadjectival verbs show a unique pattern, where the verbs productively and systematicaly contain comparative morphology.
