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.
Permanent color uses a developer (usually 10, 20, or 30 volume) to change the color fo your hair. This color is, as the name suggests, permanent. It will not wash out. Some people find that their hair will not hold permanent red hair color molecules. Usually this is caused by hair damage, but it could also be natural porosity issues. Permanent hair color is supposed to be called âhair colorâ, not âhair dyeâ. I donât know when it became the standard term, but a lot of salon professionals get really upset about it, so itâs best to use the correct term. Semi-Permanent. One of the terms you hear most when referring to crazy colors is âsemi-permanentâ.