assail vs vitriol

assail is not a noun while vitriol is a noun.

Word	Noun	Adjective	Verb	Adverb
assail	No	No	Yes	No
vitriol	Yes	No	Yes	No

As verbs, vitriol is a hyponym of assail; that is, vitriol is a word with a more specific, narrower meaning than assail:

Other hyponyms of assail include abuse, blackguard, clapperclaw, shout, claw, rip, whang, barrage, bombard, blister, scald, scorch, whip, rubbish.

assail (noun)	vitriol (noun)
	abusive or venomous language used to express blame or censure or bitter deep-seated ill will
	(H2SO4) a highly corrosive acid made from sulfur dioxide; widely used in the chemical industry

assail (verb)	vitriol (verb)
attack in speech or writing	subject to bitter verbal abuse
attack someone physically or emotionally	expose to the effects of vitriol or injure with vitriol
launch an attack or assault on; begin hostilities or start warfare with