# GMT

Source: https://englishreference.com/word/gmt
Updated: 2026-08-08

## Senses

### 1. Greenwich Mean Time

noun · CEFR B2

Stands for Greenwich Mean Time. This is the time at the 0° line of longitude in London, used to set clocks globally.

For teachers: Abbreviation for Greenwich Mean Time. The mean solar time at the Royal Observatory in Greenwich, London, serving as the baseline for the world's time zones.

- The international flight is scheduled to depart at 14:00 GMT.
- The scientific team synchronized their instruments to GMT to ensure that data collected across different continents could be accurately compared.

### 2. medical condition

noun · CEFR C2 · Technical

Stands for gelatinous bone-marrow transformation. A rare condition where bone marrow turns into a jelly-like substance, often due to severe illness.

For teachers: Abbreviation for gelatinous bone-marrow transformation. A clinicopathological entity characterized by the focal or diffuse replacement of normal bone marrow by a gelatinous substance.

- The doctor explained that GMT can occur in patients suffering from extreme malnutrition.
- Histological examination of the biopsy confirmed the presence of GMT, a finding often associated with advanced stages of anorexia nervosa or chronic infection.

Usage: Used as an uncountable noun in medical contexts.

## Examples

- The meeting starts at 10:00 AM GMT.
- International flight schedules are often listed in GMT to avoid confusion between different time zones.
- While UTC has largely replaced it for high-precision scientific applications, GMT remains the legal basis for civil time in the United Kingdom and several other nations during the winter months.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.