Getty. Much like the rest of your body, your hair goes through changes as you get older. The hair cycle -- rest, shed and grow -- slow downs, and can lead to hair loss, which can be very traumatizing. Your hair changes every seven years, explains women's hair restoration expert Lucinda Ellery. There are 150,000-200,000 hairs on our heads; we actually shed 100 a day, 36,000 in a year on average.
Definitions of yardstick. 1. measuring stick consisting of a strip of wood or metal or plastic with a straight edge that is used for drawing straight lines and measuring lengths.
countable noun. If you use someone or something as a yardstick, you use them as a standard for comparison when you are judging other people or things. There has been no yardstick by which potential students can assess individual schools before signing up for a course.