Teaspoon
There is more than one type of teaspoon:
A US teaspoon is 4.93ml: US teaspoon
A UK teaspoon is 5ml: UK teaspoon
US fluid ounces
A US fluid ounces (sometimes referred to simply as an ounce) is a unit of volume used in the United States to measure liquids. One US fluid ounce is about 0.0296 liters.