occurring, existing, or operating at the same time; concurrent
WordReference Random House Learner's Dictionary of American English © 2026
si•mul•ta•ne•ous /ˌsaɪməlˈteɪniəs, ˌsɪməl-/USA pronunciation
adj.
WordReference Random House Unabridged Dictionary of American English © 2026- existing, occurring, or operating at the same time:simultaneous translation of all speeches at the United Nations.
si•mul•ta•ne•ous
(sī′məl tā′nē əs, sim′əl-),USA pronunciation adj.
si′mul•ta′ne•ous•ly, adv.
si′mul•ta′ne•ous•ness si•mul•ta•ne•i•ty
(sī′məl tə nē′i tē, sim′əl-),USA pronunciation n.
- existing, occurring, or operating at the same time; concurrent:simultaneous movements; simultaneous translation.
- Latin simul together (see similar) + (instan)taneous
- 1650–60
- synchronous, coincident.
Collins Concise English Dictionary © HarperCollins Publishers::
'simultaneous' also found in these entries (note: many are not synonyms or translations):
Huff-Duff
- ambivalence
- arbitrage
- bipack
- bitonality
- broadside
- butterfly
- chord
- chorus
- coextrusion
- coincidence
- coincident
- coinstantaneous
- concurrence
- conflict
- conjunction
- consonance
- contemporaneous
- contemporary
- counterpoint
- cross
- crosscut
- crosscutting
- cutaway
- determinant
- diplex
- disproportionation
- dissonance
- double check
- double-check
- duplex
- elementary process
- eliminate
- elimination
- ensemble
- facilitation
- fork
- full-duplex
- fusillade
- gang saw
- group therapy
- harmony
- heterophony
- labiovelar
- lip-sync
- multiplex
- multiplexer
- multiprocessing
- objective prism
- organum