place down vs lay

place down is not a noun while lay is a noun.

Word	Noun	Adjective	Verb	Adverb
place down	No	No	Yes	No
lay	Yes	Yes	Yes	No

As verbs, lay is a hypernym of place down; that is, lay is a word with a broader meaning than place down:

Other hypernyms of place down include place, pose, position, put, set.

place down (noun)	lay (noun)
	a narrative poem of popular origin
	a narrative song with a recurrent refrain

place down (adjective)	lay (adjective)
	not of or from a profession
	characteristic of those who are not members of the clergy

place down (verb)	lay (verb)
cause to sit or seat or be in a settled position or place	put in a horizontal position
	put into a certain place or abstract location
	lay eggs
	prepare or position for action or operation
	impose as a duty, burden, or punishment