English
simultaneousness
From simultaneous + -ness.
A compound of simultaneous + -ness
Proto-Indo-European *sem- ‘one, whole’
Latin simul ‘at the same time’
Latin simultās ‘a coming together, convergence or intersection’
Medieval Latin simultaneus ‘acting together’
English simultaneous
Today it means
noun The quality or state of being simultaneous; simultaneity.
Sources
Sources: Wiktionary, “simultaneousness”. By Wiktionary contributors, CC BY-SA 4.0, via kaikki.org (dump of Oct 3 2026); text adapted and restructured. Language periods are conventional ranges, not dates for this word. License.
Etymograph / simultaneousness