The Collaborative International Dictionary
Asyndeton \A*syn"de*ton\, n. [L., fr. Gr. ?, fr. ? unconnected; 'a priv. + ? bound together, fr. ?; ? with + ? to bind.] (Rhet.) A figure which omits the connective; as, I came, I saw, I conquered. It stands opposed to polysyndeton.
Douglas Harper's Etymology Dictionary
Wiktionary
n. (context rhetoric English) A stylistic scheme in which conjunctions are deliberately omitted from a series of words, phrases, clauses.
Wikipedia
Asyndeton (from the , "unconnected", sometimes called asyndetism) is a figure of speech in which one or several conjunctions are omitted from a series of related clauses. Examples are veni, vidi, vici and its English translation "I came, I saw, I conquered". Its use can have the effect of speeding up the rhythm of a passage and making a single idea more memorable. Asyndeton may be contrasted with syndeton ( syndetic coordination) and polysyndeton, which describe the use of one or multiple coordinating conjunctions, respectively.
More generally, in grammar, an asyndetic coordination is a type of coordination in which no coordinating conjunction is present between the conjuncts.
Quickly, resolutely, he strode into the bank.
No coordinator is present here, but the conjoins are still coordinated.
It does not involve omission, but is grouped with its opposite.