mul·ti·ple / ˈməltəpəl/ • adj. having or involving several parts, elements, or members: multiple occupancy a multiple birth. ∎  numerous and often varied: words with multiple meanings. ∎  (of a disease, injury, or disability) complex in its nature or effects, or affecting several parts of the body: a multiple fracture of the femur. ∎  of or designating electrical circuits arranged in parallel. ∎  of or designating an electrical circuit that has several points at which connection can occur.• n. 1. a number that can be divided by another number without a remainder: 15, 20, or any other multiple of five.2. an arrangement of terminals that allows connection with an electrical circuit at any one of several points.

multiple consisting of many elements XVII. — F. — late L. multiplus, f. multus (see prec.); cf. duplus DUPLE.
So multiplex XVI. — L. (cf. -FOLD). multiplicity XVI. — late L. multiply XIII. — (O)F. multiplier — L. multiplicāre. multiplication XIV. — (O)F. or L. multitude XIV. — (O)F. — L.; hence multitudinous XVII.

multiple Generally, re-reflected seismic energy. More specifically, multiple reflection which is detrimental to the data and should be removed by data processing. ‘Short-path’ multiples are ghosts and near-surface phenomena; ‘long-path’ multiples, which are easier to identify and remove, are due to extra reflections deep within the subsurface.