This is the 123rd most frequent Danish word.
brug
"Brug" means "use" or "usage" in English.
"Brugt" is the past participle of 'at bruge', thus meaning 'used' or 'spent' in this context.
Hun havde ikke brugt meget tid på opgaven.
She had not spent much time on the task.
In this sentence, "bruger" is the conjugated form of 'at bruge', meaning 'to use'.
Hvordan bruger du denne maskine?
How do you use this machine?
Here, "brug" means 'need' and is used in the phrase 'have brug for', indicating necessity.