Otaheite arrowroot starch, also known as Tahitian arrowroot starch, is a type of starch that is derived from the roots of the arrowroot plant. This starch is commonly used as a thickening agent in various dishes, such as soups, sauces, and gravies. However, if you are looking for alternatives to this starch, there are several synonyms that you can consider. For example, you can use tapioca starch, cornstarch, potato starch, or rice flour as substitutes. These alternatives have similar properties to Otaheite arrowroot starch and can thicken liquids to the desired consistency. It's important to note that the amount of alternative starch used may need to be adjusted to achieve the same thickening effect.