1 [I,T] (formal 正式) to spread sth or become spread widely in all directions （使）扩散，分散

2 [I,T] (technical术语) if a gas or liquid diffuses or is diffused in a substance, it becomes slowly mixed with that substance （气体或液体在另一物质中）扩散

3 [T] (formal 正式) to make light shine less brightly by spreading it in many directions 使（光线）漫射 ➔diffusion /dɪˈfju:ʒn ||; dɪˈfjuʒən/ noun [C]