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1.
adverb: by mistake, unintentional

verb: the whole thing
person1: I accidentally the whole bottle.
person 2: What?
Person1: You know when you and then the bottle gets stuck?
Person1: oh wow, that sucks man.
by Kaplowawow December 08, 2008
 
2.
transitive verb, past tense: To break beyond repair, or lose completely, or do something catastrophic or highly objectionable or problematic to. Ostensibly by accident but most often used ironically for a purposeful act.
I accidentally the whole thread.

I accidentally the whole website.

I accidentally your mom.

I accidentally inside her.
by ann ong June 30, 2010
 
3.
Verb:

To make mistakes in a sentence such that the sentence is impossible to comprehend. Usually when a verb, adjective, noun or pronoun is misplaced or missing. Failing to put a period can lead to an accidentally (components of one sentence can be confused to be in another. Thus misplaced components).

Usually used by the person responding to the sentence as a form of irony (since accidentally is an adjective, so using it as a verb would mean it is misplaced).

Using an accidentally is an accidentally.
Example 1: Missing pronoun

Person 1: I cant believe not coming.

Person 2: What? I think you accidentally your post.

Example 2: Missing period {2 options}

Person 1: She was running {period} until 5pm {period} I was watching TV

Person 2: What? I think you are missing a period. You accidentally there.
by Die Nacht December 03, 2010