An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

1) Making no sound; quiet; still.
2) Refraining from speech.

From L. silentem (nominative silens) "still, calm, quiet," p.p. of silere "to be quiet or still," of unknown origin.

Bideng, from Kurd. (Kurmanji) bêdeng, bêdêng, Kurd. (Sorani) bedang, from bi- "without," → a-, + deng "sound, voice," variants dong, dang, bâng, → Big Bang.