Plants that obtain some or all of their nutrients directly from a host plant are called parasitic plants.

Here's a breakdown:

* Parasitic plants: These plants lack the ability to produce their own food through photosynthesis. Instead, they rely on a host plant for sustenance, tapping into its vascular system to steal water, nutrients, and sometimes even sugars.

* Holoparasites: These are completely reliant on their host plant for survival. They lack chlorophyll and cannot photosynthesize at all.

* Hemiparasites: These can photosynthesize to some extent but still rely on their host plant for some essential nutrients and water.

Some examples of parasitic plants include:

* Mistletoe: A hemiparasite that grows on the branches of trees.

* Rafflesia: A holoparasite that is known for its giant flower.

* Dodder: A holoparasite that grows in a vine-like form and can smother its host plant.