A hanger-on, or one who lives at another's expense.

依附他人者；依人为生者。

A useless person, doing no work, but living in comfort at the expense of others.

清客；食客；寄食者。

An animal or plant which lives on or within another at the latter's expense, as lice, disease germs, and the various blights.

寄生动植物(如虱、病菌及各种作物害虫)。