noun
Refers to a biological parasite or a person who lives off others. The term is neutral in biological contexts but can be derogatory when applied to people.
その虫は他の昆虫に寄生する寄生者だ。
That insect is a parasite that lives off other insects.
彼は親に頼ってばかりの寄生者のような生活を送っている。
He leads a parasitic lifestyle, always depending on his parents.