International Grandmaster

The title Grandmaster is awarded to world-class chess masters by the world chess organization FIDE. Apart from "World Champion", Grandmaster is the highest title a chess player can attain. It is a lifetime title, in chess literature usually abbreviated as GM (this is in contrast to FM for FIDE Master and IM for International Master). The abbreviation IGM for International Grandmaster can also sometimes be found, particularly in older literature. GM, IM, and FM are open to both men and women. Beginning with Nona Gaprindashvili in 1978, a number of women have earned the GM title. Since about 2000, most of the top 10 women have held the GM title.
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Noun
1. a chess player who has been awarded the highest title by an international chess organization
(hypernym) grandmaster