* Conversion: There are approximately 6 teaspoons in 1 fluid ounce.

* Calculation:

* One eighteenth of a teaspoon is equal to (1/18) teaspoon.

* To find the equivalent in ounces, divide this by 6: (1/18) teaspoon / 6 teaspoons/ounce = 1/108 ounce.

Therefore, one eighteenth of a teaspoon is approximately equal to 1/108 ounce.