Brown rice and Rice

Brown rice noun - Unpolished rice retaining the yellowish-brown outer layer.

Rice and brown rice are semantically related. In some cases you can use "Rice" instead a noun phrase "Brown rice".

Rice noun - Annual or perennial rhizomatous marsh grasses; seed used for food; straw used for paper.

Brown rice and rice are semantically related. Sometimes you can replace phrase "Brown rice" with "Rice", this terms are similar.