noun, noun which may take the genitive case particle 'no'
Used as a noun or with の to mean 'all of something' or 'the entirety'. Often appears in formal or emphatic contexts.
All responsibility lies with me.
彼は一切の財産を失った。
He lost all of his property.
absolutely (not); (not) at all; (none) whatsoever
Used adverbially with a negative verb to mean 'not at all' or 'absolutely not'. Stronger than 全然.
彼は一切お酒を飲まない。
He doesn't drink alcohol at all.
その件については一切知りません。
I know absolutely nothing about that matter.
He didn't answer that question at all.
I left all the preparations to her.
I will take full responsibility for everything.
一切 is typically paired with negative verbs to mean 'not at all' or 'none whatsoever', while ことごとく is used affirmatively to mean 'every single one without exception'.
all worldly affairs; everything in life
complete set of household goods; all household belongings
all expenses; total cost