This is the 2586th most frequent Korean word.
부작용이
"Side effect."
In this sentence, "부작용이" (side effects) is used to describe potential negative reactions to a prescribed drug.
그 약은 부작용이 나타날 수 있습니다.
That medicine may cause side effects.
Here, "부작용이" refers to the undesirable effects caused by the use of a product.
이 제품의 부작용이 상당히 적습니다.
This product has very few side effects.
In this example, "부작용이" is used to denote the listed side effects included in an instruction manual.