agonising vs torturing

agonising is not a noun while torturing is a noun.

Word	Noun	Adjective	Verb	Adverb
agonising	No	Yes	No	No
torturing	Yes	Yes	No	No

As adjectives, agonising and torturing are synonyms defined as:

Other synonyms of agonising include agonizing, excruciating, harrowing, torturesome, torturous.

agonising (noun)	torturing (noun)
	the deliberate, systematic, or wanton infliction of physical or mental suffering by one or more persons in an attempt to force another person to yield information or to make a confession or for any other reason

agonising (adjective)	torturing (adjective)
extremely painful	extremely painful