δρόσος

Dew is condensed water from the air that adheres on solid cool objects. This happens, for instance, in the night after sunny warm days: with the absence of the Sun, the air cools and shrinks causing the water that it carries to drop out of the air and condense on the gras, on plant leaves, on spider webs etc. and, of course, also on human's instruments, e.g. on telescopes of astronomers. Most people recognise the dew only in the morning when they get up and it glitters in the first beams of sunshine but the dew emerges during the whole night.