Sī’mul-tā’ne-oūs, a.

(Synop., § 130), a. [L. Lat. simultaneus, from Lat. simul, at the same time, together; It. & Sp. simultāneo, Fr. simultané.] Existing or happening at the same time; as, simultaneous events.

Simultaneous equations (Math.), equations in which the values of the unknown quantities entering them are the same in both or in all at the same time.