General. The prime consideration when using abbreviations should be to help the reader. First, then, they should be easily understood. So when an abbreviation that may not be familiar to readers first occurs, it is best to write out the full term followed by the abbreviation in brackets:
- The emissions trading scheme (ETS) should enable the EU to meet its Kyoto target.
If your document contains a lot of abbreviations, consider including a list of them and their meanings at the beginning or end of the document.
Secondly, they should not be used needlessly. If an abbreviation occurs only once or twice, it is best to dispense with it altogether and use the full form. In repeated references, it is also often possible to use a short form instead of an abbreviation:
- The emissions trading scheme is now in operation throughout the EU … The scheme will involve constant monitoring of emissions trading activities.
Lastly, an abbreviation in an original for translation should not be rendered by an improvised one in English (e.g. repeated references to ‘VM’ in an Estonian text should be spelled out as ‘the Foreign Ministry’ or just ‘the Ministry’ rather than something like ‘FM’).
Definitions. Abbreviations in the broad sense can be classed into two main categories, each in turn divided into two sub-categories:
Acronyms and initialisms
- Acronyms are words formed from the first (or first few) letters of a series of words, and are pronounced as words (Benelux, NATO). They never take points.
- Initialisms are formed from the initial letters of a series of words, usually written without points, and each separate letter is pronounced (BBC, MEP, USA).
Contractions and truncations
- Contractions omit the middle of a word (Mr, Dr) and, in British usage, are not followed by a point.
- Truncations omit the end of a word (Feb., Tues.) and sometimes other letters as well (cf.), and end in a point.
Acronyms with five letters or less are uppercased:
- AIDS, COST, ECHO, EFTA, NASA, NATO, SHAPE, TRIPS
- Exceptions: Tacis and Phare, which are no longer considered acronyms
Acronyms with six letters or more should normally be written with an initial capital followed by lower case. Thus:
- Benelux, Esprit, Helios, Interreg, Resider
- Exceptions: organisations that themselves use upper case (such as UNESCO and UNCTAD) and other acronyms conventionally written in upper case (such as WYSIWYG)
Note, however, that some acronyms eventually become common nouns, losing even the initial capital, e.g. laser, radar or sonar.
Initialisms are usually written in capitals, whatever their length, and take no points:
- EEA, EAGGF, EMCDDA, UNHCR, WTO, also AD for Anno Domini and NB for Nota Bene
If the full expressions are lower-case or mixed-case, however, the initialisms may follow suit:
- aka, BAe (British Aerospace), cif, fob, MoD, PhD, TfL (Transport for London)
To ensure clarity, initialisms written in lower case may take points or be italicised:
- f.o.b. or fob, c.i.f. or cif
Note that ‘e.g.’ and ‘i.e.’ are never capitalised (even at the beginning of footnotes) and always take points. In contrast, ‘plc’ (public limited company) is usually without points even if written in lower case.
Truncations take a point at the end:
- Jan., Sun., Co., fig., etc., cf., chap., dict., ibid.
- Note also: St. (= Street; as distinguished from the contraction St = Saint) and p. = page (plural: pp.); l. = line, (plural: ll.)
Note that any plural forms are regarded as truncations rather than contractions, so also take a point:
- chs. 7 to 9, figs. 1 to 3
However, truncated forms used as codes or symbols, e.g. EN, kg, do not take points (see also 5.20 and 5.29). Further, no point is used after the v in the names of court cases (Smith v Jones) and sporting contests. The abbreviation No for ‘number’ (plural Nos) also has no final point, as it is in fact a contraction of the Latin numero.
Note that first names should be abbreviated with a single letter only, followed by a point (Philippe: P., Theodor: T.). Multiple initials should normally be written with points and separated by a hard space (Key code for Windows: Alt + 0160. In Word, press Ctrl + Shift + Space.) (J. S. Bach). For compound first names, use both initials (Jean-Marie: J.-M.).
As in the case of e.g. and i.e., some common truncations are traditionally never written in upper case — even at the beginning of a footnote (c. [=circa], p., pp., l., ll. [= line/s]).
Indefinite article. Apply the rule ‘a before a consonant, an before a vowel’ as if the abbreviation following the article were being spoken:
- a UN resolution, a WTO representative, a NATO decision
Acronyms constituting proper names do not take the definite article even if the full names do (Cenelec, NATO, Unesco). Where used as common nouns, however, they take a definite (or indefinite) article as necessary (a/the BLOB, WASP).
Initialisms generally take the definite article if the expression they stand for does (the OECD, the WTO, but TNT). However, there is a tendency to drop the article if the initialism is regarded more as a name in its own right, for example where the full expression is hardly ever used or no longer even known. Bare initialisms are also seen as ‘cooler’, which probably explains DGT for the Directorate-General for Translation.
Plurals. Plurals of abbreviations are formed in the usual way by adding a lower-case ‘s’ without an apostrophe:
- DGs, ICTs, OCTs, PhDs, SMEs, UFOs
While an abbreviation ending in ‘S’ should also take an ‘s’ for the plural form, e.g. SOSs, this looks clumsy if it is often used in the plural. In such cases, the abbreviation may be taken to stand for both the singular and the plural form, e.g. MS (Member State(s)), PES (public employment service(s)) or RES (renewable energy source(s)), so does not need an extra ‘s’.
Foreign-language abbreviations. Untranslated foreign-language abbreviations should retain the capitalisation conventions of the original (e.g. GmbH).
Use of e.g. and i.e. Use a comma, colon, or dash before e.g. and i.e., but no comma after them. If a footnote begins with them, they nevertheless remain in lower case. If a list begins with e.g. do not end it with etc.
Do not use the abbreviation viz., but use namely instead. The abbreviation cf., however, is acceptable and need not be changed to see.
Article may be abbreviated to Art. in footnotes or tables, but this should be avoided in running text.
Foreign-language conventions. Remember that languages may have different conventions as regards their use of mathematical symbols, especially those for multiplication, division, and subtraction.
Many mathematical symbols also have several different meanings according to the context.
Multiplication sign. Change a point or a raised dot used as a multiplication sign to × or *, e.g. 2.6 . 1018 becomes 2.6 × 1018 or 2.6 * 1018 . A point used in an algebraic expression can be omitted, e.g. 2.A = 2.π.r2 can be written 2A = 2πr2 .
Note, however, that a raised dot can have other meanings too.
Division sign. In the English-speaking world, the commonest symbols for division are ÷ , / , and ∕ (obelus (You will find it in the Latin-1 character set after the letter ö, using Insert > Symbol … in Word.), slash, and solidus or division slash 9In the Mathematical Operators character set, using Insert > Symbol … in Word)). In other countries : (colon) is very widely used to denote division.
Note that in some countries (Norway, for one) ÷ can denote subtraction (!), and in Italy it can also denote a range (e.g. 40 % ÷ 50 % means 40 to 50 per cent).
Open dashes. Use a closed-up en dash, not a hyphen or open dash, to signify a range (e.g. 10–12 %).
Technical tolerances. Do not use ± (ASCII 241) to mean ‘about’ or ‘approximately’. Use it only for technical tolerances.
Per cent. Note that per cent is normally written as two words in British English. Use per cent where the number is also spelled out in words: twenty per cent. With figures, use the per cent sign (%) preceded by a thin space (Key code for Windows: Alt + 8201. However, this does not display correctly on Commission PCs using older versions of Windows and Office. In such cases, insert a hard space (Ctrl + Shift + Space in Word) and then halve the space width (in Word: Format, Font, Character Spacing, Scale = 50 %). If this is not practicable, use a normal hard space.), e.g. 25 %.
Observe the distinction between per cent (or %) and percentage point(s): an increase from 5 % to 7 % is an increase of two percentage points (or an increase of 40 %), not an increase of 2 %.
Percentages. Express percentage relationships in running text economically, especially when translating: un taux de 65 % par rapport à la totalité des exportations en dehors de l’Union européenne translates simply as 65 % of EU exports.
SCIENTIFIC SYMBOLS AND UNITS OF MEASUREMENT
General. Most scientific symbols in current use are interlingual forms and do not require any adaptation when writing in English. In the specific case of weights and measures, the International System of Units (SI — Système International) has now been adopted almost universally for science and technology, as well as generally for trade and industry in the EU. For further guidance, see the UK Metric Association’s ‘Measurement units style guide’.
Names of measurement units. Names of basic and derived units of measurement are always lowercased even if they are derived from a personal name, e.g. ampere, kelvin, hertz, newton, pascal, watt, siemens, becquerel. They have normal plurals in -s: 250 volts, 50 watts, etc.
Note that proper names used adjectivally retain their initial capital: Richter scale, Mach number, degree Celsius.
Symbols for units of measurement. These are normally abridged forms of the names of these units. They are written without stops, do not have plurals, and are separated from preceding figures by a hard space (Key code for Windows: Alt + 0160. In Word, press Ctrl + Shift + Space.) (4 ha, 9 m, 60 km, 50 km/h, 200 g, 5 kg, 40 t, 20 bar, 55 dB (A), 2 000 kc/s).
Capitalisation/lowercasing of symbols. The initial letter of symbols for SI units derived from personal names is always capitalised: Hz (hertz), Bq (becquerel), N (newton), K (kelvin), etc. Symbols derived from generic nouns are always lowercased and are the same for both singular and plural: g (gram), kg (kilogram), lm (lumen), lx (lux), mol (mole), cd (candela), etc.
Internal capitals. Symbols for units of measurement that start with a capital letter keep the capital internally when used with a prefix: kHz, MHz, eV, etc.
Use of prefixes. When adding prefixes to units, you should normally link either symbols only or full-forms only: thus kilohertz or kHz but not kiloHz or khertz. Exceptions are made for some frequently used terms: ktonnes/Mtonnes, kbits/Mbytes.
Non-SI units of measurement. Some non-metric units of measurement are still permitted for certain purposes, e.g. the pint in Ireland and the UK and miles and yards in the UK. Greece uses the stremma (1 000 square metres) for land measurement. Aircraft altitudes are often expressed in feet (ft). Do not convert quantities, although an explanatory footnote may be inserted if appropriate.
Degree sign. The degree sign in temperatures should be preceded by a thin space (Key code for Windows: Alt + 8201. However, this does not display correctly on Commission PCs using older versions of Windows and Office. In such cases, insert a hard space (Ctrl + Shift + Space in Word) and then halve the space width (in Word: Format, Font, Character Spacing, Scale = 50 %). If this is not practicable, use a normal hard space.), e.g. 25 °C. In other cases, the degree sign is closed up with the preceding number (e.g. 65°NE).
Ohm. The ohm symbol is capital omega (Ω). All other SI symbols for units of measurement are formed from unaccented Latin characters.
Computing. Where computers are concerned, K (kilo), M (mega) and G (giga) often stand for binary thousands (1 024=210), millions (1 048 576=220) and billions (1 073 741 824=230), respectively. Note the capital K in this usage.
Electric power. Kilowatt (kW) and megawatt (MW) are used for generating capacity, kWh and MWh for output over a given period.
Chemical elements. The names of the chemical elements start with a lowercase letter, including elements whose designations are derived from proper names: californium, einsteinium, nobelium, etc. Their symbols (which are interlingual) consist either of a single capital or a capital and small letter (N, Sn, U, Pb, Mg, Z) without a point.
In shipping, grt stands for gross register tonnage (not registered) and gt for gross tonnage.