veg vs greens

veg and greens both are nouns.

Word	Noun	Adjective	Verb	Adverb
veg	Yes	No	No	No
greens	Yes	No	No	No

As nouns, greens is a hyponym of veg; that is, greens is a word with a more specific, narrower meaning than veg:

veg: edible seeds or roots or stems or leaves or bulbs or tubers or nonsweet fruits of any of numerous herbaceous plant
greens: any of various leafy plants or their leaves and stems eaten as vegetables

veg (noun)	greens (noun)
edible seeds or roots or stems or leaves or bulbs or tubers or nonsweet fruits of any of numerous herbaceous plant	any of various leafy plants or their leaves and stems eaten as vegetables