tidal river vs tidal stream

tidal river and tidal stream both are nouns.

Word	Noun	Adjective	Verb	Adverb
tidal river	Yes	No	No	No
tidal stream	Yes	No	No	No

As nouns, tidal river and tidal stream are synonyms defined as:

tidal river and tidal stream: a stream in which the effects of the tide extend far upstream

Other synonyms of tidal river include tidewater river, tidewater stream.

tidal river (noun)	tidal stream (noun)
a stream in which the effects of the tide extend far upstream	a stream in which the effects of the tide extend far upstream