Synonyms for Simultaneously:

adv.

at the same time (adverb)
synchronously, as one, concurrently, together.
simultaneously (adverb)
contemporaneously, coincidentally, concurrently, synchronously, Concomitantly.

adv

concurrently (adverb)
all at once.
simultaneously (adverb)
contemporaneously, coincidentally, concurrently, synchronously, Concomitantly.
together (adverb)
concurrently, as one, all together, contemporaneously.

n.

as one, together. all at once, time, accompanied, all together. simultaneously (noun)
at the same time.

Other synonyms:

together. Other relevant words:
at the same time, all together, together, as one, all at once, time.

Usage examples for simultaneously

  1. We reached the station simultaneously with the seven ten. – The Brother of Daphne by Dornford Yates
  2. Elijah the Prophet, in his ancient mantle, had been seen everywhere simultaneously drinking the wine- cups left out for him, and sometimes filling them with oil. – Dreamers of the Ghetto by I. Zangwill