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THESAURUS
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WORDNET DICTIONARY

Adverbial simultaneously has 1 sense

• simultaneously(r = adv.all) at the same time - at the same instant; "they spoke simultaneously"

THESAURUS

simultaneously

all at once, all together, as one, as one man, at a blow, at a clip, at a stroke, at once, at one blow, at one jump, at one stroke, at one swoop, at one time, at that time, coincidentally, coinstantaneously, concurrently, contemporaneously, forthwith, in a chorus, in a hurry, in chorus, in concert with, in phase, in sync, in unison, isochronously, now, on that occasion, on the beat, per saltum, pronto, right away, right now, right off, straightaway, straightway, subito, synchronously, then, then and there, this minute, this very minute, together, uno saltu, with one voice, without delay

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simultaneously

Synchronism

N synchronism, coexistence, coincidence, simultaneousness, simultaneity, concurrence, concomitance, unity of time, interim, isochronism, contemporary, coetanian, synchronous, synchronal, synchronic, synchronical, synchronistical, simultaneous, coexisting, coincident, concomitant, concurrent, coeval, coevous, contemporary, contemporaneous, coetaneous, coeternal, isochronous, at the same time, simultaneously, together, in concert, during the same time, in the same breath, pari passu, in the interim, as one, at the very moment, just as, as soon as, meanwhile.

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