Definition

In OCEANOG­RAPHY, the property of water to transmit light of dif­ferent WAVE LENGTHS. Transpa­rency sometimes is measured in percent of RADIATION that penetrates a distance of one METRE. Sometimes it is expressed as the average DEPTH at which a SECCHI DISC disappears and reappears. In PHOTOGRAPHY, a photogra­phic PRINT on a clear base, especially adaptable for viewing by transmitted light. Also, the light-transmitting capability of a material.