# langley

/ˈɫæŋɡɫi/ (US)

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

## Senses

### 1. the CIA

noun · CEFR C1 · American English

a name people use to talk about the Central Intelligence Agency (CIA) in the United States.

For teachers: a metonym for the Central Intelligence Agency, derived from the location of its headquarters in Langley, Virginia.

- The news report said that Langley is investigating the new security threat.
- Analysts at Langley were reportedly skeptical of the intelligence gathered by the field office during the initial stages of the operation.

Usage: Usually used without an article when referring to the organization itself.

### 2. unit of radiation

noun · CEFR C2 · Technical

a technical unit used to measure how much solar energy hits a surface.

For teachers: a unit of heat transmission or solar radiation equivalent to one calorie per square centimetre.

- The scientist recorded the daily solar energy in langleys.
- The total solar radiation received at the surface was measured in langleys to determine the rate of evaporation in the arid region.

Usage: The symbol for this unit is Ly.

## Examples

- The sensor measures the langleys of solar energy hitting the field.
- Meteorologists recorded the daily langleys to determine if the solar panels were operating at peak efficiency during the summer.
- The total solar radiation received at the surface was expressed in langleys to facilitate a direct comparison with historical climate data from the mid-twentieth 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.