# IRS

/ˈaɪˌɑˈɹɛs/ (US)

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

## Senses

### 1. US tax agency

noun · CEFR B2 · American English

Stands for Internal Revenue Service. This is the U.S. government office that collects taxes from people and businesses.

For teachers: Abbreviation for Internal Revenue Service. The federal agency of the United States government responsible for tax collection and the enforcement of internal revenue laws.

- You must send your tax return to the IRS by the middle of April.
- The IRS conducted a thorough audit of the corporation's offshore accounts to ensure compliance with recent changes in federal tax legislation.

### 2. navigation system

noun · CEFR C1 · Technical

Stands for Inertial Reference System. A piece of equipment in an airplane that helps it find its position without using outside signals.

For teachers: Abbreviation for Inertial Reference System. A self-contained navigation system that uses gyroscopes and accelerometers to calculate a vehicle's position, orientation, and velocity.

- The pilot checked the IRS display to confirm the aircraft's current coordinates.
- Modern long-haul aircraft typically utilise a triple-redundant IRS to maintain navigational accuracy during transoceanic flights where ground-based signals are unavailable.

### 3. financial contract

noun · CEFR C1 · Technical · Formal

Stands for Interest Rate Swap. A contract where two parties trade interest rate payments with each other.

For teachers: Abbreviation for Interest Rate Swap. A derivative contract in which two counterparties exchange one stream of future interest payments for another, based on a specified principal amount.

- The company used an IRS to change their variable rate loan into a fixed rate.
- Institutional investors often employ an IRS to hedge against potential fluctuations in market interest rates over the duration of a long-term bond.

## Examples

- I need to send my tax return to the IRS by April.
- The IRS recently updated its online portal to help citizens track their tax refunds more efficiently.
- Small business owners must maintain meticulous financial records to ensure they remain in compliance with the complex regulations enforced by the IRS.

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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.