Name given to the festive palm-branch which with the Etrog, are carried and waved on the Jewish Feast of Tabernacles (Sukkot).
The three constituents of the Lulav are:
(1) A shoot of the palm-tree in its folded state before the leaves are spread out (also called Lulav) ; this must be at least three handbreadths long, so that it may be waved, and must be bound round with a twig or tendril of its own kind; (2) Hadas - three twigs of myrtle of the species which has its leaves in whorls of three; and (3) Arava - two willow-branches of the kind of which the wood is reddish and the leaves are long and entire. The myrtle-twigs and willow-branches are tied to the lower end of the palm-branch—the former on the right, and the latter on the left—by means of three rings of palm-strips.
These branches, together with the Etrog constitute the "Four species" ("arba'at haminim").
Adapted from 1901 - 1906 public domain Jewish Encyclopedia