tidal river vs tidewater stream

tidal river and tidewater stream both are nouns.

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

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

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

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

tidal river (noun)	tidewater 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