item vs part

item and part both are nouns.

Word	Noun	Adjective	Verb	Adverb
item	Yes	No	No	Yes
part	Yes	No	Yes	Yes

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

item: a whole individual unit; especially when included in a list or collection
part: an item that is an instance of some type

Other hyponyms of item include custom-built, custom-made, disposable, piece, number.

As nouns, part is a hypernym of item; that is, part is a word with a broader meaning than item:

item: a distinct part that can be specified separately in a group of things that could be enumerated on a list
part: something determined in relation to something that includes it

Other hypernyms of item include component, component part, constituent, portion.

As nouns, part is a hypernym of item; that is, part is a word with a broader meaning than item:

Other hypernyms of item include component, component part, constituent, portion.

item (noun)	part (noun)
a whole individual unit; especially when included in a list or collection	the actions and activities assigned to or required or expected of a person or group
an isolated fact that is considered separately from the whole	the effort contributed by a person in bringing about a result
a distinct part that can be specified separately in a group of things that could be enumerated on a list	something less than the whole of a human artifact
an individual instance of a type of symbol	an item that is an instance of some type
a small part that can be considered separately from the whole	a line of scalp that can be seen when sections of hair are combed in opposite directions
	one of the portions into which something is regarded as divided and which together constitute a whole
	an actor's portrayal of someone in a play
	that which concerns a person with regard to a particular role or situation
	the melody carried by a particular voice or instrument in polyphonic music
	the extended spatial location of something
	a portion of a natural object
	assets belonging to or due to or contributed by an individual person or group
	something determined in relation to something that includes it

item (verb)	part (verb)
	move or break apart
	force, take, or pull apart
	depart for someplace
	go one's own way; move apart
	discontinue an association or relation; go different ways

item (adverb)	part (adverb)
(used when listing or enumerating items) also	to some extent; in some degree; not wholly