An Etymological Dictionary of Astronomy and Astrophysics

In theoretical physics, an entity which can have any number of allowed spatial dimensions. It is usually accompanied by a prefix, i.e. p-brane, indicating the number of dimensions. For example, a 0-brane is a zero-dimensional point-like particle, a 1-brane is a → string, a 2-brane is a “membrane,”
and so forth. Our Universe is a 3-brane.

Etymology (EN): Brane, short for membrane, from L. membrana “parchment,” from membrum “limb, member of the body,” → member.

Etymology (PE): Breyn, loanword from E., as above.