The aim of the study is to examine the effect of sentential context on lexical ambiguity resolution in Greek adults and typically developing children. Context and word frequency are factors that can affect lexical processing, however, the role of them has not been thoroughly examined in Greek. To this aim, we assessed sentence context effects in homonym meaning activation in monolingual speakers of Greek, children and adults, using a cross-modal priming paradigm. Additionally, all participants conducted a verbal working memory task and an inhibition task so as to examine whether the use of sentential context for lexical ambiguity resolution relates to age and/or cognitive processing capacity. The data analysis showed (a) major processing differences between adults and children due to ambiguity and sentential context, (b) children's processing times affected by cognitive skills while adults' processing unaffected, and (c) visual word recognition intact for all participants.