Diffusion (noun). the act of diffusing, or the state of being diffused; a spreading; extension; dissemination; circulation; dispersion. Diffusion (noun). the act of passing by osmosis through animal membranes, as in the distribution of poisons, gases, etc., through the body.
Learner's definition of EXCITEMENT. 1. [noncount] : a feeling of eager enthusiasm and interest : the state of being excited. Our excitement was building/growing/mounting as the end of the game approached. His hands shook with excitement. The child cried out in excitement.
an exciting or very unusual experience. 2. participation in exciting undertakings or enterprises: the spirit of adventure. 3. a bold, usually risky undertaking; hazardous action of uncertain outcome. 4. a commercial or financial speculation of any kind; venture.