piece of paper vs slip

piece of paper and slip both are nouns.

Word	Noun	Adjective	Verb	Adverb
piece of paper	Yes	No	No	No
slip	Yes	No	Yes	No

As nouns, slip is a hyponym of piece of paper; that is, slip is a word with a more specific, narrower meaning than piece of paper:

Other hyponyms of piece of paper include slip of paper, signature, folio, leaf, tear sheet, foolscap, style sheet, worksheet, revenue stamp, stamp.

piece of paper (noun)	slip (noun)
paper used for writing or printing	a flight maneuver; aircraft slides sideways in the air
	a socially awkward or tactless act
	the act of avoiding capture (especially by cunning)
	an unexpected slide
	a minor inadvertent mistake usually observed in speech or writing or in small accidents or memory lapses etc.
	a woman's sleeveless undergarment
	bed linen consisting of a cover for a pillow
	artifact consisting of a narrow flat piece of material
	a small sheet of paper
	a slippery smoothness
	an accidental misstep threatening (or causing) a fall
	a place where a craft can be made fast
	a young and slender person
	a part (sometimes a root or leaf or bud) removed from a plant to propagate a new plant through rooting or grafting
	potter's clay that is thinned and used for coating or decorating ceramics

piece of paper (verb)	slip (verb)
	fall to a lower standard
	move out of position
	insert inconspicuously or quickly or quietly
	to make a mistake or be incorrect
	pass out of one's memory
	move obliquely or sideways, usually in an uncontrolled manner
	move stealthily
	move easily
	move smoothly and easily
	cause to move with a smooth or sliding motion
	pass on stealthily