Fl. oz. is a term commonly used to represent fluid ounces in the United States. However, there are several synonyms for this term that are used in different parts of the world. In the UK, for example, the term is frequently replaced with "imperial fluid ounce" or "UK fluid ounce." Other common synonyms in use include "fluid ounces," "liquid ounces," "fluid oz.," "fl oz," "oz. liq," and "oz. fl." Regardless of the term used, one fluid ounce is equivalent to approximately 29.5 milliliters. It is important to verify the unit of measurement before using it to avoid any confusion.