Diffuse, a.
Etymology: [L. diffusus, p. p.]
Poured out; widely spread; not restrained; copious; full; esp., of style, opposed to concise or terse; verbose; prolix; as, a diffuse style; a diffuse writer. A diffuse and various knowledge of divine and human things. Milton.
Syn. -- Prolix; verbose; wide; copious; full. See Prolix.
2 other Webster entries under this spelling
Diffuse, v. t. [imp. & p. p. Diffused; p. pr. & vb. n. Diffusing.]
To pour out and cause to spread, as a fluid; to cause to flow on all sides; to send out, or extend, in all directions; to spread; to circulate; to disseminate; to scatter; as to diffuse information. Thence diffuse His good to worlds and ages infinite. Milton. We find this knowledge diffused among all civilized nations. Whewell.
Syn. -- To expand; spread; circulate; extend; scatter; disperse; publish; proclaim.
Diffuse, v. i.
To pass by spreading every way, to diffuse itself.
Shades of meaning
Fernald lists diffuse only as an antonym, under terse.
He lists it without comment; the entries above explain its neighbors.