The term 'Brain Layer' refers to the CORTEX, which is a six-letter word. The CORTEX is the outermost layer of the brain and is responsible for higher-level functions such as language, memory, and consciousness. It is composed of gray matter and is divided into four distinct lobes: frontal, parietal, temporal, and occipital. The CORTEX is essential for complex cognitive processes and is the most highly evolved part of the human brain.