quietly

adv. quedamente, calladamente, en silencio, quedo, silenciosamente, sin bombo ni platillos, sin hacer ruido; recogidamente, con tranquilidad, quietamente, retiradamente, sosegadamente, tranquilamente

quedamente, calladamente, en silencio, con discreción

Ex: This technology matured quietly, until desktop workstations became available around 1983.

= de un modo discreto
Ex: This technology matured quietly, until desktop workstations became available around 1983.
----
* quietly spoken = que habla en voz baja