n.[C][(+on/of)]

1. 寄生生物；攀附植物
2. 【喻】寄生虫
   The lazy man was a parasite on his family.

   那懒汉是他家的一个寄生虫。

3. （古希腊）食客

n.

1. an organism which lives in or on another organism and benefits by deriving nutrients at the other's expense.
2. derogatory a person who habitually relies on or exploits others and gives nothing in return.