As for the etymology the term enemy is derived from Latin language for 'bad friend' (Latin: inimicus). Enemy is a strong word, and emotions associated with the enemy would include anger, hatred, frustration, envy, jealousy, fear, distrust, and possibly grudging respect . As a political concept, an enemy is likely to be met with hate, violence, battle and war. The opposite of an enemy is a friend or ally.
diffusion. 1. The process of rapid random movement of the particles of a liquid or gas which eventually form a uniform mixture. 2. The mixing of substances due to the motion of their particles.
Brownian Motion. Diffusion is the movement of particles from high concentration to low concentration in a substance. This process is essential for life on Earth, allowing for the movement of molecular compounds into and out of the cell. All matter in the universe is in motion, because all molecules are vibrating.