This is the 1069th most frequent Russian word.
пожар
Fire (uncontrolled).
Here, 'пожар' (fire) is used as a noun to denote a destructive fire.
Пожар уничтожил старый амбар.
The fire destroyed the old barn.
In this sentence, 'пожар' is used in a general sense to discuss the concept of a fire event.
На уроке безопасности обсуждали, как предотвратить пожар.
During the safety class, they discussed how to prevent a fire.
Here, 'пожар' refers to a specific past event of a fire that caused damage.