Odyssey is an oft-used word that means unusual or peculiar. However, there are several other words that can be used as synonyms for oddball. For example, eccentric is a term used to describe someone who is unconventional in their thinking or behavior. Another word that can be used is idiosyncratic, which means a person who has peculiar habits or beliefs. Quirky is another useful word that describes someone or something that is unconventional or odd. Offbeat is an alternative term that can be used, suggesting an individual or an idea that is unusual or unconventional. In short, these words all convey the sense of being different, unique, or out-of-the-ordinary.