Definition
If something is described as being 'before someone's time,' it means that it occurred or existed before that person was born or was old enough to remember it.
（某事物）在某人出生或記事之前
I don't really know much about vinyl records; they were before my time.
我不太了解黑膠唱片；它們在我出生之前就存在了。
My memory of that old theater is hazy; it was before my time.
我對那家老劇院的記憶很模糊；它在我記事之前就存在了。
I've never heard of that band; it seems they broke up before my time.
我從未聽說過那個樂團；他們似乎在我出生之前就解散了。