A volcano, which is not active, but is still registering seismic activity When there is no more seismicity, the volcano is dormant, but still capable of erupting (see active, dormant, extinct)
causing no symptoms; "a quiescent tumor" being quiet or still or inactive not active or activated; "the quiescent level of centimeter wave-length solar radiation" marked by a state of tranquil repose; "the quiescent melancholy of the town
Someone or something that is quiescent is quiet and inactive. a society which was politically quiescent and above all deferential. + quiescence qui·es·cence a long period of quiescence. not developing or doing anything, especially when this is only a temporary state (present participle of quiescere; QUIET)
Not in active mode, "asleep" Typically this word is used in our specifications in conjunction with current drain in order for the customer to develop a power budget