item vs news item

item and news item both are nouns.

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

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

item: a distinct part that can be specified separately in a group of things that could be enumerated on a list
news item: an item in a newspaper

Other hyponyms of item include agenda item, incidental, inventory item, line item, place, position.

item (noun)	news item (noun)
a whole individual unit; especially when included in a list or collection	an item in a newspaper
an isolated fact that is considered separately from the whole
a distinct part that can be specified separately in a group of things that could be enumerated on a list
an individual instance of a type of symbol
a small part that can be considered separately from the whole

item (adverb)	news item (adverb)
(used when listing or enumerating items) also