An Etymological Dictionary of Astronomy and Astrophysics

One of the organs, usually green and flat, growing from the side of a stem or branch or direct from the root of a tree or plant. A leaf constitutes a unit of the foliage, and functions primarily in food manufacture by → photosynthesis.

Etymology (EN): M.E. leef, lef; O.E. leaf; cf. O.S. lof, O.N. lauf, O.Fris. laf, Du. loof, O.H.G. loub, Ger. Laub.

Etymology (PE): Barg “leaf” (Tabari, Gilaki valg, balg; Kurd. belg, balk, Semnâni valg); Mid.Pers. warg “leaf;” Av. varəka- “leaf;” cf. Skt. valká- “bark, bast, rind;” Russ. volokno “fibre, fine combed flax.”