As an initialism GM
is game master; game moderator.
As a noun Grandmaster is
the highest title a chess player can attain; also called International Grandmaster; abbreviated GM or IGM.
gm
Translingual
Symbol
(
head)
The ISO 3166-1 two-letter (alpha-2) code for Gambia.
ISO 3166-1
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grandmaster
English
Noun
(
en noun)
The highest title a chess player can attain; also called International Grandmaster ; abbreviated GM or IGM.