shepherd vs tend

shepherd is a noun but tend is not a noun.

Word	Noun	Adjective	Verb	Adverb
shepherd	Yes	No	Yes	No
tend	No	No	Yes	No

As verbs, tend is a hypernym of shepherd; that is, tend is a word with a broader meaning than shepherd:

shepherd (noun)	tend (noun)
a herder of sheep (on an open range); someone who keeps the sheep together in a flock
a clergyman who watches over a group of people

shepherd (verb)	tend (verb)
tend as a shepherd, as of sheep or goats	have care of or look after
watch over like a shepherd, as a teacher of her pupils	manage or run
	have a tendency or disposition to do or be something; be inclined