*SET-U

English word origin

Etymology of RER

From French RER, often reinterpreted as "Regional Express Rail".

1 source sectionBrief source recordWiktionary original ↗
In this entry · 1 source sections

The source etymologies

Wiktionary via Kaikki / Wiktextract

The source reports below are imported and unreviewed by *SET-U. Separate numbered origins and differing source variants are preserved; agreement within this extraction is not independent corroboration.

Unnumbered source etymology

Original entry ↗
name

Any of many RER systems in French-speaking countries. · GO Expansion, a project to improve commuter rail in Ontario.

noun

A type of railway system that generally runs from suburbs or satellite towns into a city centre, with a central tunnel or overground corridor with higher speeds and more widely spread stations than a subway or metro.

Selected source glosses provide context, not a complete modern definition inventory

From French RER, often reinterpreted as "Regional Express Rail".

Relationships mentioned by the source

These are extracted mentions, not a timeline or a verified sequence of immediate parents.

  • Borrowed-form mentionRERfr
Inspect preserved source fields

Raw extraction fields are retained for auditing. Their order does not establish ancestry.

{
  "templates": [
    {
      "name": "borrowed",
      "args": {
        "1": "en",
        "2": "fr",
        "3": "RER"
      },
      "expansion": "French RER"
    }
  ],
  "links": [
    [
      "RER",
      "RER#French"
    ]
  ],
  "references": [],
  "descendants": [],
  "lexical": [
    {
      "pos": "name",
      "glosses": [
        "Any of many RER systems in French-speaking countries.",
        "GO Expansion, a project to improve commuter rail in Ontario."
      ],
      "tags": [],
      "recordId": "4443d2aa966ad48ede715000a14021274f3bd88c717913f5f8b48b54faa8f81c",
      "rawRecordSha256": "b31b7046c87b29f5e1c4c77abcb8bcdd99ce13b09a70c62a6a903b5cb37e91ae",
      "sourceRecordOrdinal": 1577586
    },
    {
      "pos": "noun",
      "glosses": [
        "A type of railway system that generally runs from suburbs or satellite towns into a city centre, with a central tunnel or overground corridor with higher speeds and more widely spread stations than a subway or metro."
      ],
      "tags": [],
      "recordId": "66972ed52a2212caf2822dccc522108e23bbc3dea24ba43869675ac3fdbc8a0b",
      "rawRecordSha256": "41334f8cbe8948a14a7a6338782f753e89bd269c4988dae9b18bde99e3978622",
      "sourceRecordOrdinal": 1577585
    }
  ],
  "omittedAuxiliaryFields": {
    "templates": 0,
    "links": 0,
    "references": 0,
    "descendants": 0,
    "lexicalRecords": 0,
    "lexicalSenses": 0,
    "glosses": 0
  }
}

Where this record stops

This page does not supply an independently verified sound-change sequence, first-use manuscript or complete family tree unless a cited analysis explicitly establishes one. Missing detail here is a limit of this record—not a claim that humanity knows nothing more.

An older meaning does not determine what a word must mean today. Follow the sources, preserve disagreements, and keep ancestry separate from interpretation.

Contribute located evidence for RER →

Source and snapshot

Imported from Wiktionary contributors; extracted by Tatu Ylonen / Wiktextract / Kaikki.org. Selected fields are reformatted and grouped; wording, source identity and etymology sections are retained. CC-BY-SA-4.0 applies to the imported source material.

Dump: 2026-10-01 · Extracted: 2026-10-30. These are snapshot dates, not the word’s first attestation or the page’s revision date.

Source entry and bibliography ↗Wiktionary revision history ↗Acquisition and rights ledger
Machine-source provenance
Source SHA-256
5ff2c072f8099f2d2ce484bd6957bf179f046d2ad37bc36555edf8bb84cb5291
Import run
73216b9a9b78ed3830994bf853103716f5a4dc57099e371e9f8fdc468facca26
Permanent entry ID
w-UkVS