# meridian

/mɝˈɪdiən/ (US) · /mɛɹˈɪdiən/ (UK)

Source: https://englishreference.com/word/meridian
Updated: 2026-08-15

## Senses

### 1. line of longitude

noun · CEFR B2 · Technical

an imaginary line on the Earth's surface that goes from the North Pole to the South Pole.

For teachers: a great circle on the Earth's surface passing through the geographic poles, used to measure longitude.

- The Prime Meridian passes through Greenwich in London and marks zero degrees longitude.
- Navigators calculate their east-west position by measuring the time difference between their local noon and the time at the prime meridian.

Usage: Often used with 'prime' to refer to the 0° longitude line.

### 2. highest point

noun · CEFR C1 · Literary

the time when something is at its most successful or powerful point.

For teachers: the point of highest development or perfection; a figurative peak or zenith.

- The empire reached its meridian during the eighteenth century before slowly losing power.
- Historians often debate whether the poet was at the meridian of his creative powers when he wrote his final epic.

Teaching tip: This sense is literary; in modern everyday speech, 'peak' or 'height' is much more common.

### 3. energy pathway

noun · CEFR C1 · Technical

any of the paths in the body that energy is said to flow through in traditional Chinese medicine.

For teachers: in traditional Chinese medicine, any of the pathways through which 'qi' or life force flows.

- Acupuncture involves placing needles at specific points along a meridian to improve health.
- The practitioner explained that the treatment was designed to clear blockages in the lung meridian and restore balance to the body.

### 4. celestial circle

noun · CEFR C2 · Technical

an imaginary circle in the sky that passes through the poles and the point directly above you.

For teachers: a great circle passing through the celestial poles and the zenith of a particular location.

- The star will be at its highest point when it crosses the local meridian tonight.
- Astronomers wait for a celestial body to transit the meridian to take the most accurate measurements of its altitude.

## Examples

- The Prime Meridian passes through Greenwich in London.
- Navigators use the local meridian to determine the exact moment of noon when the sun reaches its highest point.
- The establishment of a universal prime meridian was essential for synchronizing global maritime charts and creating a standardized system of international time zones during the nineteenth century.

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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.