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ERA Railway Terminology visual v0 featured

ERA Railway Terminology Collection

Last updated: 5 December 2025.

The ERA Railway Terminology Collection gathers terms and abbreviations that are contained in the EU legal framework for railway, technical documents produced by bodies which are engaged in the development of important evolution in the railway system and other relevant glossaries.

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The file you will get by clicking the "Download the full Terminology" button below is in CSV format. To convert it to a readable Excel file:

1. Download the CSV file
2. Open a blank Excel sheet
3. Go to Data → Get Data from CSV → select the CSV file you just downloaded
4. The Excel file will be generated (without any encoding issues)

Starting with "U" (165)

ERA Railway Terminology Collection is a consultation tool, developed to support the sharing of information through the actors involved in running the Single European Railway Area (SERA). The responsibility for the correctness, completeness, accuracy, or reliability of the information in ERA RTC lays upon the authors of the definitions, as they derive from reference documents having their own preparation and approval flow. Users cannot call ERA liable for the use they make of the content. Please consider that when the collection is exported (.csv) and then printed or converted, it becomes uncontrolled.
Term Context Document Type Origin document

Unit

Freight

TSI

Commission Regulation (EU) No 321/2013 of 13 March 2013 concerning the technical specification for interoperability relating to the subsystem ‘rolling stock — freight wagons’ of the rail system in the European Union and repealing Decision 2006/861/EC

Unit capacity used

Telematics Applications for Freight

TSI

Commission Regulation (EU) No 1305/2014 of 11 December 2014 on the technical specification for interoperability relating to the telematics applications for freight subsystem of the rail system in the European Union and repealing the Regulation (EC) No 62/2006

Unit costs

EU Policy

Glossary

The Social Costs of Transport - February 1997

Unit in operation

Freight

TSI

Commission Regulation (EU) No 321/2013 of 13 March 2013 concerning the technical specification for interoperability relating to the subsystem ‘rolling stock — freight wagons’ of the rail system in the European Union and repealing Decision 2006/861/EC

Unit load

Freight

Glossary

Terminology on Combined Transport from Economic Commission for Europe (UN/ECE). Prepared by the UN/ECE, the European Conference of Ministers of Transport (ECMT) and the European Commission (EC). UNITED NATIONS - New York and Geneva, 2001

Unit Load

Telematics Applications for Freight

TSI

Commission Regulation (EU) No 1305/2014 of 11 December 2014 on the technical specification for interoperability relating to the telematics applications for freight subsystem of the rail system in the European Union and repealing the Regulation (EC) No 62/2006

Unit load

RNE Glossary

Glossary

RNE Glossary - NS_CID_Glossary_2025

Latest release

Unit train

Telematics Applications for Freight

TSI

Commission Regulation (EU) No 1305/2014 of 11 December 2014 on the technical specification for interoperability relating to the telematics applications for freight subsystem of the rail system in the European Union and repealing the Regulation (EC) No 62/2006

Unit train

RNE Glossary

Glossary

RNE Glossary - NS_CID_Glossary_2025

Latest release

Universal design

Persons with Reduced Mobility

Decision

Council Decision of 26 November 2009 concerning the conclusion, by the European Community, of the United Nations Convention on the Rights of Persons with Disabilities

Universal toilet

Persons with Reduced Mobility

Regulation

Commission Regulation (EU) No 1300/2014 of 18 November 2014 on the technical specifications for interoperability relating to accessibility of the Union's rail system for persons with disabilities and persons with reduced mobility.

Unladen vehicle weight

EU Policy

Glossary

Eurostat Transport Glossary on web

Unloader

International Relations

Convention

Convention concerning International Carriage by Rail (COTIF) Appendix C – Regulations concerning the International Carriage of Dangerous Goods by Rail (RID)

Unloader

Safety / SSC-SA

Directive

Directive (EU) 2016/798 of the European Parliament and of the Council of 11 May 2016 on railway safety (recast)

Unloader

RNE Glossary

Glossary

RNE Glossary - NS_CID_Glossary_2025

Latest release

Unloading

International Relations

Convention

Convention concerning International Carriage by Rail (COTIF) Appendix C – Regulations concerning the International Carriage of Dangerous Goods by Rail (RID)

UNMS SR

International Standard

EU Technical Document

CEN CENELEC ABBRAVIATION ACRONYM 2025

Latest release

UNMZ

International Standard

EU Technical Document

CEN CENELEC ABBRAVIATION ACRONYM 2025

Latest release

Unprotected wrong side failure

ERTMS

Technical Document

ERTMS/ETCS - Glossary of Terms and Abbreviations - version : 4.0.0 - date 05/07/2023

UNRRA

EU Policy

EU Technical Document

Technical document from the Publications Office of the European Union - ‘Style guide’ Coordination Interinstitutional Style Guide - version on 19.04.2022