Ultraviolet index. The ultraviolet index or UV Index is an international standard measurement of the strength of sunburn-producing ultraviolet (UV) radiation at a particular place and time. The scale was developed by Canadian scientists in 1992, then adopted and standardized by the UN's World Health Organization and World Meteorological Organization in 1994.
one-quarter-one of four equal parts; a quarter of a pound. fourth part, one-fourth, quarter, quartern, twenty-five percent, fourth. common fraction, simple fraction-the quotient of two integers.
DEFINITION of 'Quarter - Q1, Q2, Q3, Q4'. A three-month period on a financial calendar that acts as a basis for the reporting of earnings and the paying of dividends. The four quarters that make up the year are: January, February and March (Q1); April, May and June (Q2); July, August and September (Q3); and October, November and December (Q4). A quarter is often shown with its relevant year, as in Q1 2015 or Q1/15, which represents the first quarter of the year 2015.