(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.
n. pl. cat's-eyes. 1  1. Any of various semiprecious gems such as chrysoberyl, BeAl2O4, reflecting a band of light that shifts position as the gem is turned. 2  2. A glass or plastic reflector designed to glow in the beam of a headlight, used on a vehicle as a safety device or set in rows along a highway as lane markers.