Simultaneous (adjective)

1. Occurring or operating at the same time.
2. Occurring or existing together or in the same period of time.
3. Occurring or done at the same instant.
4. Having the same point in time.
5. Happening at the same time.

Origin:

Late 16th century: from french simultané or late latin simulaneus, from simul "at the same time".

Examples:

1. The two events were simultaneous.
2. We heard the simultaneous sound of the two explosions.
3. The simultaneous translation made it easy for the international audience to understand.
4. The simultaneous launch of the two rockets was a success.
5. The simultaneous release of the movie in different countries was a first for the studio.