(Redirected from Weighted mean) In colloquial language, an average is the sum of a list of numbers divided by the number of numbers in the list. In mathematics and statistics, this would be called the arithmetic mean. In statistics, mean, median, and mode are all known as measures of central tendency.
Definition of cat'sâeye for English Language Learners. : 1  a jewel that has a pale stripe running down its middle which makes it look like the eye of a cat. : 2  a marble with round circles that look like eyes.
Cats eye Color. The quality of this gem is judged by the display of chatoyancy effect. A catâs-eye ( Chatoyancy) is the band of light that runs length wise from one end of the stone to the other. Chatoyancy is caused by a parallel needle or a hollow tube like inclusion inside the gem.