Grey matter is a term used to refer to the parts of the BRAIN that are made up of nerve cells and their connections. It is often used to describe the BRAIN's ability to think, reason, and remember. The crossword solutions for the term grey matter include BRAIN (5 letters), BRAINS (6 letters), CORTEX (6 letters), MIND (4 letters), and INTELLECTUAL (12 letters). BRAIN and BRAINS refer to the physical organ, while CORTEX, MIND, and INTELLECTUAL refer to the mental processes associated with grey matter.