toilet tissue vs tissue

toilet tissue and tissue both are nouns.

Word	Noun	Adjective	Verb	Adverb
toilet tissue	Yes	No	No	No
tissue	Yes	No	Yes	No

As nouns, tissue is a hypernym of toilet tissue; that is, tissue is a word with a broader meaning than toilet tissue:

Other hypernyms of toilet tissue include tissue paper.

toilet tissue (noun)	tissue (noun)
a soft thin absorbent paper for use in toilets	part of an organism consisting of an aggregate of cells having a similar structure and function
	a soft thin (usually translucent) paper

toilet tissue (verb)	tissue (verb)
	create a piece of cloth by interlacing strands of fabric, such as wool or cotton