Albizia julibrissin is known by a wide variety of common names, such as Persian silk tree or pink siris. It is also called Lenkoran acacia or bastard tamarind, though it is not too closely related to acacias (Acacieae), let alone tamarinds (Caesalpinioideae). The species is usually called "silk tree" or "mimosa" in the United States, which is misleading - the former name can refer to any species of Albizia which is most common in any one locale. And although once included in Mimosa, it is neither very close to the Mimoseae. To add to the confusion, several species of Acacia, notably Acacia baileyana and Acacia dealbata, are also known as "mimosa" (especially in floristry), and many Fabaceae trees with highly divided leaves are called thus in horticulture.
Its leaves slowly close during the night and during periods of rain, the leaflets bowing downward as if the tree were sleeping: its modern Persian name shabkhosb (شبخسب) means "night sleeper" (from shab شب "night" and -khosb خسب "sleeper"). In Japan its common names are nemunoki, nemurinoki and nenenoki which all mean "sleeping tree". Nemu tree is a partial translation of nemunoki.
