GR
Abbreviation with 3 meanings
| Stands for | Greece |
|---|---|
| Meanings | 3 |
| Categories | Geography & Places, Science & Engineering, Units & Measurements |
| Also written | gr |
GR has three meanings. The most common are Greece (country code) and General relativity (physics); it can also stand for Grain.
Meanings of GR at a glance
| # | GR stands for | Context |
|---|---|---|
| 1 | Greece | Geography & Places › Country Code |
| 2 | General relativity | Science & Engineering › Physics |
| 3 | Grain | Units & Measurements › US Customary and Imperial Unit |
1. Greece
Geography & Places · Country Code Abbreviations
Greece's code, alpha-3 GRC, with Athens as its capital. Greek VAT numbers are an exception in the EU: they begin with EL, from Ellas, rather than GR.
Example: Greek IBANs start with GR and contain 27 characters.
Sports bodies use GRE. The language code for Greek is el. The .gr domain and the GR vehicle sign follow the ISO code, while the EU uses EL in many official contexts.
2. General relativity
Science & Engineering · Physics Abbreviations
Albert Einstein's theory of gravity, published in 1915, which describes gravity not as a force but as the curvature of spacetime by mass and energy. GR predicts the bending of light, black holes, gravitational waves and the slowing of clocks in strong gravity, and it underlies modern cosmology.
Example: Without GR corrections, GPS positions would drift by about 10 kilometers per day.
Arthur Eddington's 1919 eclipse expedition confirmed GR's prediction that starlight bends near the Sun, making Einstein world-famous. GPS satellite clocks gain about 45 microseconds per day from weaker gravity and lose about 7 from their speed, a net 38 microseconds that must be corrected. GR has not yet been reconciled with quantum mechanics.
3. Grain (gr)
Units & Measurements · US Customary and Imperial Unit Abbreviations · also used in medicine
The smallest unit in the avoirdupois, troy and apothecary systems, exactly 64.79891 milligrams; 7,000 grains make a pound. Bullet and arrow-point weights and gunpowder charges are measured in grains.
Example: Load a 55 gr bullet over 25 grains of powder for the varmint rifle.
The unit originally represented the weight of a single grain of barley or wheat. A standard 325 mg aspirin tablet descends from the old 5-grain dose. Do not confuse gr with g (gram), which is about 15.4 times larger; this mix-up has caused medication errors in older prescriptions.
Related abbreviations
More country code abbreviations
- GM – Gambia
- GN – Guinea
- GP – Guadeloupe
- GQ – Equatorial Guinea
- GRE – Greece
- GS – South Georgia and the South Sandwich Islands
- GT – Guatemala
- GW – Guinea-Bissau
See all 270 country code abbreviations →