The cat stalked ?wilily around the house: Morphological dissimilation in deadjectival adverbs

The adverbial suffix -ly₁ and the adjectival suffix -ly₂ typically do not combine (e.g., *ghost+ly₂+ly₁; 'in a ghostlike manner'). However, phonologically similar strings are attested when one /li/ string is part of the word stem (jollily, compared to: ?smellily, *lovelily). Does morphological structure modulate the acceptability of these words independently from the impact of phonological or usage-based constraints? In two experiments, jolly-type stems are rated more acceptable than smell- and love-type stems, which did not significantly differ from each other. A combination of phonological constraints and increased morphological complexity can account for the observed pattern.