# LOS

/ˈɫoʊs/ (US)

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

## Senses

### 1. line of sight

noun · CEFR B2 · Technical

Stands for Line of Sight. It describes a straight, clear path between two points, like a person's eyes and an object.

For teachers: Abbreviation for Line of Sight. It refers to an unobstructed path between a transmitter and a receiver, or between an observer and a target.

- The two radio towers need a clear LOS to communicate effectively.
- Urban planners must consider the LOS from the historic monument to ensure that new skyscrapers do not obstruct the view.

Usage: Usually functions as an uncountable noun or a modifier before another noun.

### 2. loss of signal

noun · CEFR C1 · Technical

Stands for Loss of Signal. You use this when a connection, like a radio or satellite link, is broken.

For teachers: Abbreviation for Loss of Signal. It denotes the total interruption of a telemetric or communication link.

- The ground crew reported LOS as the spacecraft moved behind the moon.
- Engineers monitored the telemetry feed closely, noting the exact second of LOS during the atmospheric reentry phase.

Usage: Commonly used in aerospace and telecommunications contexts.

### 3. level of service

noun · CEFR C1 · Technical

Stands for Level of Service. It is a measure used to describe how well a road or utility is working.

For teachers: Abbreviation for Level of Service. A qualitative measure used by engineers to describe operational conditions within a traffic stream or utility network.

- The new highway project aims to improve the LOS during rush hour.
- The city council reviewed the LOS metrics for the public water system to determine if infrastructure upgrades were necessary.

Usage: Frequently used in civil engineering and public administration.

## Examples

- They shall los their way in the dark woods.
- The ancient manuscript warns that those who seek the treasure may los their very souls in the process.
- In the solemn verses of the old hymn, the faithful are reminded that to find one's life, one must first be willing to los it for a higher cause.

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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.