1. (Physiology) the faculty or sense by which sound is perceived. 2. an opportunity to be listened to. 3. (General Physics) the range within which sound can be heard; earshot. 4. (Law) the investigation of a matter by a court of law, esp the preliminary inquiry into an indictable crime by magistrates. 5.
The grey hair ârule of thumbâ is that by the age of 50, half of the population have lost the colour in 50% of their hair. When researchers tested this rule, they found that 74% of people aged between 45 and 65 had grey hair, with an average intensity of 27%. Generally, men have more grey hair than women.
Hair color experts study the theory of color pigment. It is only through understanding hair pigments and correct color formulations that the correct color can be chosen and applied to hair color clients.uite simply hair coloring is the science and art of changing the color of the hair. The natural color of human hair is first and foremost directly tied to hereditary factors. As scientists have proven, hair color is an inherited characteristic.