n. The operation of cutting open or separating into parts. Specificallyn. The process of cutting into parts an animal or a plant, or a part of one, in such a way as to show its structure or to separate one or more of its organs or tissues for examination: as, the dissection of a dog; the dissection of a hand or a flower.n. n. The act of separating anything into distinct or elementary parts for the purpose of critical examination; treatment or consideration of something in detail or point by point.n. A segment; a division; a part.n. In botany, the condition of being dissected. See dissected.n. In geology, the erosion of a land-surface into numerous irregular valleys. See dissect, 4.