spread vs diffuse

spread is a noun but diffuse is not a noun.

Word	Noun	Adjective	Verb	Adverb
spread	Yes	Yes	Yes	No
diffuse	No	Yes	Yes	No

As verbs, spread and diffuse are synonyms defined as:

As verbs, diffuse is a hyponym of spread; that is, diffuse is a word with a more specific, narrower meaning than spread:

As verbs, spread and diffuse are synonyms defined as:

Other synonyms of spread include fan out, spread out.

spread (noun)	diffuse (noun)
act of extending over a wider scope or expanse of space or time
decorative cover for a bed
farm consisting of a large tract of land along with facilities needed to raise livestock (especially cattle)
a haphazard distribution in all directions
the expansion of a person's girth (especially at middle age)
a conspicuous disparity or difference as between two figures
two facing pages of a book or other publication
process or result of distributing or extending over a wide expanse of space
a tasty mixture to be spread on bread or crackers or used in preparing other dishes
a meal that is well prepared and greatly enjoyed

spread (adjective)	diffuse (adjective)
distributed or spread over a considerable extent	(of light) transmitted from a broad light source or reflected
fully extended in width	spread out; not concentrated in one place
prepared or arranged for a meal; especially having food set out	lacking conciseness

spread (verb)	diffuse (verb)
cause to become widely known	cause to become widely known
become widely known and passed on	spread or diffuse through
distribute or disperse widely	move outward
spread out or open from a closed or folded state
become distributed or widespread
cover by spreading something over
distribute over a surface in a layer
strew or distribute over an area
move outward
spread across or over