This is the 9934th most frequent Russian word.
алкоголем
"Алкоголем" means "alcohol" (instrumental case) in English.
Here, 'алкоголем' is in the instrumental case, denoting the means by which the action is accomplished—alcohol being the item offered.
Он угощал гостей алкоголем.
He treated his guests with alcohol.
In this sentence, 'алкоголем' is used in the instrumental case, indicating the tool or means by which an action is performed—in this case, disinfection.
Алкоголем можно дезинфицировать раны.
Alcohol can be used to disinfect wounds.
'Алкоголем' appears in the instrumental case here to specify the entity that should not be misused—alcohol.