Astandard drink of hard liquor is ounces.

A standard drink of hard liquor is 0.6 fluid  ounces.

Explanation:

Liqueur is a sweetened drink made from alcohol and fruits, herbs, spices, flowers, seeds, roots, tree bark and whatever you want, plus something sweet like sucrose, honey or glucose is also included. A standard liquor drink is 0.6 fluid ounces.

This drink was born in the Middle Ages when wine was the main type of antiseptic they had there. However, roots, herbs and plants were constantly studied by monks in an attempt to cure diseases and illnesses that existed at the time.