adjective
simultaneous
sigh-mul-TAY-nee-us/ˌsaɪmlˈteɪniəs/
Happening or existing at the same time.
The runners' simultaneous finishes occur at precisely the same instant.
Etymology
Latin simultaneus expresses shared timing, ultimately from simul, “at the same time.” Its precise formation is uncertain, but the central idea is separate events sharing one time.
In context
I can experience two events that to me seem to have happened at the same time. They are simultaneous events.
More examples
- The twins give simultaneous answers to the question.
- The lab measures simultaneous changes in temperature and pressure.
- Two simultaneous power failures leave the neighborhood in darkness.
Forms
simultaneous
simultaneously adverb — At exactly the same time.
simultaneity noun — The fact of happening at the same time.
Similar words
- concurrent
- Often describes overlapping periods rather than one exact moment.
- synchronous
- Often emphasizes coordinated timing or matching rhythms between processes.