In the present article, we explore the morphological semantics of Modern Greek (MG) and how these are expressed in ontological terms in the MMoOn ontology. First, we define the two core aspects of meaning, grammatical and lexical, pointing out that there are also other more abstract types of meaning such as derivational that pertain to affixes or confixes. Most prominently, we explore the transition of features of morphemic components to the output derivational structures, a process most commonly known as percolation theory. In order to ensure the consistency of the process, we specify an automated way of this transfer as well as the types of the transmitted features for each different case. To this end, we leverage OWL expressive language, defining appropriate classes, object properties and chain properties in the Protégé ontology editor. Afterwards, we confirm that the syntax works well by checking out the generated inferences. In the research to come, more investigation on morphemic semantics of MG is to be done touching upon other aspects of it.