Reference
Text, dialogue, lyrics, and/or images of alcohol would be considered references.
Use
The use/consumption of alcohol in any case would constitute use.
Encourages/Glamorizes
If characters gain advantage or achieve success after the use of alcohol, this would be considered encouragement/glamorization. This includes prominent advertising for real-world brands explicitly encouraging the use of alcohol (e.g., a frothy beer mug with the words "You know you want it"; a couple telling the audience that "X Brand Beer is the tastiest").