Music can be a powerful mnemonic device, as shown by a body of literature demonstrating that listening to text sung to a familiar melody results in better memory for the words compared to conditions where they are spoken. Furthermore, patients with a range of memory impairments appear to be able to form new declarative memories when they are encoded in the form of lyrics in a song, while unable to remember similar materials after hearing them in the spoken modality. Whether music facilitates the acquisition of completely new information, such as new vocabulary, remains unknown. Here we report three experiments in which adult participants learned novel words in the spoken or sung modality. While we found no benefit of musical presentation on free recall or recognition memory of novel words, novel words learned in the sung modality were more strongly integrated in the mental lexicon compared to words learned in the spoken modality. This advantage for the sung words was only present when the training melody was familiar. The impact of musical presentation on learning therefore appears to extend beyond episodic memory and can be reflected in the emergence and properties of new lexical representations.