accidentally

adv. incidentally, by chance

For alternate meanings, see: Accident (fallacy), Accident (philosophy), Accident (film), Accident, Maryland, and Car accidents. An accident is a specific, identifiable, unexpected, unusual and unintented external event which occurs in a particular time and place, without apparent cause but with marked effect. It implies a generally negative probabilistic outcome which may have been avoided or prevented had circumstances leading up to the accident been recognized, and acted upon, prior to its occurrence.
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Adverb
1. without advance planning; "they met accidentally"
(synonym) by chance, circumstantially, unexpectedly
(antonym) intentionally, deliberately, designedly, on purpose, purposely, advisedly, by choice, by design
(pertainym) accidental, casual, chance(a)
2. in an incidental manner; "these magnificent achievements were only incidentally influenced by Oriental models"
(synonym) incidentally, by chance
3. without intention; in an unintentional manner; "she hit him unintentionally"
(synonym) unintentionally
(antonym) intentionally, deliberately, designedly, on purpose, purposely, advisedly, by choice, by design
(pertainym) accidental, inadvertent

(adv.)
In an accidental manner; unexpectedly; by chance; unintentionally; casually; fortuitously; not essentially.
  

adverb
(a) by chance; I found the missing watch accidentally
(b) in an accident; he was killed accidentally