give off vs radiate

give off is not an adjective while radiate is an adjective.

Word	Noun	Adjective	Verb	Adverb
give off	No	No	Yes	No
radiate	No	Yes	Yes	No

As verbs, radiate is a hyponym of give off; that is, radiate is a word with a more specific, narrower meaning than give off:

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

Other hyponyms of give off include effuse, reflect, shine, spark, sparkle, scintillate, fume, smoke, reek, shoot, ray, steam.

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

give off (verb)	radiate (verb)
have as a by-product	send out real or metaphoric rays; the children radiated joyous energy
give off, send forth, or discharge; as of light, heat, or radiation, vapor, etc.	issue or emerge in rays or waves
	spread into new habitats and produce variety or variegate
	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