In a common household 1/2 ounces of cough syrup would be given with a table spoon, or even a regular spoon.
Explanation:
Most cough syrup's don't come with withe the little cups to help measure the amount of cough syrup to be taken. Therefore people use spoons, which might be a table spoon. The probability of someone using a table spoon is 50/50 because, there are various types of spoons out there.
That being said your answer would be: Spoon/Table spoon.