Cistus, with its many hybrids and cultivars, is commonly encountered as a garden flower. The common name rockrose is applied to the species, a name also shared by the related genera Halimium, Helianthemum and Tuberaria, all in the family Cistaceae. The common name gum cistus is applied to resin-bearing species, especially C. ladanifer.
Quasars are part of a class of objects known as active galactic nuclei (AGN). Other classes include Seyfert galaxies and blazars. All three require supermassive black holes to power them.
quail. n, pl quails or quail. 1. (Animals) any small Old World gallinaceous game bird of the genus Coturnix and related genera, having a rounded body and small tail: family Phasianidae (pheasants). 2. (Animals) any of various similar and related American birds, such as the bobwhite.