まるっきり

まるっきり means "completely", and with a negative "not at all". It is a casual, emphatic adverb that goes before the verb or adjective it strengthens, and most of the time that is a negative.

"Completely" in an affirmative sentence

Without a negative, まるっきり says something is wholly so, usually that it has changed out of recognition or is the exact opposite of something.

まるっきり, まるきり and まったく

まるっきり is the emphatic form of まるきり, with the same meaning. Both are conversational and carry some surprise or exasperation. In writing or formal speech, use まったく for "not at all" and かんぜん完全に for "completely".