1. gr - Noun
2. Gr - Proper noun
GR
(Britain) Initialism of George Rex. (on coins, letterboxes, etc.) The royal cypher for George V and his son George VI, kings of Great Britain
Hyponyms: GVR, GVIR
(biochemistry) Initialism of glucocorticoid receptor.
(physics) Initialism of general relativity.
(sports) Initialism of games record.
Abbreviation of grain, a unit of mass.
(rare) Abbreviation of gram; the standard symbol for gram since the International System of Units was introduced in 1960 is g.
Source: en.wiktionary.org