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.
Time Frame. Underarm hair can begin to grow as late as age 17, with 96 percent of teens seeing their first growth by the time they're 15, and 95 percent reporting full growth by the time they're 19. Growth occurs slowly, with an average of 3 to 4 years from the time that hair begins to grow until a complete region of growth is reported.