radiate vs emit

radiate is an adjective but emit is not an adjective.

Word	Noun	Adjective	Verb	Adverb
radiate	No	Yes	Yes	No
emit	No	No	Yes	No

As verbs, emit is a hypernym of radiate; that is, emit is a word with a broader meaning than radiate:

radiate: send out real or metaphoric rays; the children radiated joyous energy
emit: expel (gases or odors)

Other hypernyms of radiate include breathe, pass off.

As verbs, emit is a hypernym of radiate; that is, emit is a word with a broader meaning than radiate:

radiate: send out rays or waves
emit: give off, send forth, or discharge; as of light, heat, or radiation, vapor, etc.

Other hypernyms of radiate include give off, give out.

radiate (adjective)	emit (adjective)
having rays or ray-like parts as in the flower heads of daisies
arranged like rays or radii; radiating from a common center

radiate (verb)	emit (verb)
send out real or metaphoric rays; the children radiated joyous energy	expel (gases or odors)
issue or emerge in rays or waves	express audibly; utter sounds (not necessarily words)
spread into new habitats and produce variety or variegate	give off, send forth, or discharge; as of light, heat, or radiation, vapor, etc.
experience a feeling of well-being or happiness, as from good health or an intense emotion
cause to be seen by emitting light as if in rays
have a complexion with a strong bright color, such as red or pink
extend or spread outward from a center or focus or inward towards a center
send out rays or waves