Sound symbolism is the notion that the relation between word sounds and word meaning is not arbitrary for all words, but rather there is a subset of words in the world's languages for which sounds and their symbols have some degree of correspondence. This research investigates sound symbolism as a possible means of gaining semantic knowledge of unknown words within written context. Two studies assessed adults' expressive knowledge of word meanings for sound symbolic and non-sound symbolic obsolete words. These words were presented in varying types of contextual surroundings: no context, varied context, unhelpful context, and helpful context. In each study, participants were able to generate more correct definitions for sound symbolic words compared to non-sound symbolic words. It is concluded that sound symbolism is a word property which influences the learning of unknown words.