Semitic languages exhibit rich nonconcatenative morphological operations, which can generate a myriad of
derived lexemes. Especially, the feature rich, root-driven morphology in the Arabic language demonstrates the
construction of several verb-derived nominals (verbal nouns) such as gerunds, active participles, passive
participles, locative participles, etc. Although HPSG is a successful syntactic theory, it lacks the
representation of complex nonconcatenative morphology. In this paper, we propose a novel HPSG representation for
Arabic nominals and various verb-derived nouns. We also present the lexical type hierarchy and derivational rules
for generating these verb-derived nominals using the HPSG framework.