The term 'ORGAN LAYER' can be broken down into two words, 'ORGAN' and 'LAYER'. The first word, 'ORGAN', refers to a body part or structure that is composed of tissues and cells that work together to perform a specific function. The second word, 'LAYER', refers to a thin sheet or LAYER of material. When combined, the term 'ORGAN LAYER' refers to a thin sheet or LAYER of tissue or cells that make up an ORGAN. The crossword solution for this term is 'CORTEX', which is a type of ORGAN LAYER found in the brain. CORTEX is a thin LAYER of neurons that are responsible for higher-level thinking, decision-making, and other cognitive functions.