I. dif ‧ fuse 1 /dɪˈfjuːz/ BrE AmE verb
[ Date: 1300-1400 ; Language: Old French ; Origin: diffuser , from Latin diffusus , past participle of diffundere 'to spread out' ]
1 . [intransitive and transitive] to make heat, light, liquid etc spread through something, or to spread like this
diffuse through/into/across
The pollutants diffuse into the soil.
2 . [intransitive and transitive] to spread ideas or information among a lot of people, or to spread like this:
Their ideas diffused quickly across Europe.
3 . [transitive] to make a bad feeling or situation less strong or serious:
an attempt to diffuse his anger
—diffusion /dɪˈfjuːʒ ə n/ noun [uncountable]
II. dif ‧ fuse 2 /dɪˈfjuːs/ BrE AmE adjective
[ Date: 1400-1500 ; Language: Latin ; Origin: diffusus ; ⇨ ↑ diffuse 1 ]
1 . spread over a large area:
The organization is large and diffuse.
2 . using a lot of words and not explaining things clearly and directly:
His writing is diffuse and difficult to understand.
—diffuseness noun [uncountable]