noun
: a wave in which the vibrating element (as the electric field in light waves or the particles of a vibrating medium) moves in a direction perpendicular to the direction in which the wave advances
noun
: a wave in which the vibrating element (as the electric field in light waves or the particles of a vibrating medium) moves in a direction perpendicular to the direction in which the wave advances
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012