This chapter is from the book
This chapter is from the book
This chapter is from the book
Abbreviations
Abbreviations allow writers to avoid cumbersome repetition of lengthy words and phrases. They are a form of shorthand and are appropriate in technical and business writing, particularly in lists, tables, charts, graphs, and other visual aids where space is limited. See ACRONYMS.
Eliminate periods in and after most abbreviations.
Formerly, most abbreviations required periods. Today, the trend is to eliminate periods in and after abbreviations, especially in the abbreviated names of governmental agencies, companies, private organizations, and other groups:
NOTE 1: The abbreviations covered by this rule do not include informal ones such as Dept. and Mgt., which use a final period but no periods between letters.
NOTE 2: By convention, some abbreviations still require periods:
Retain the period, too, in abbreviations that spell normal words:
- in., inches (not in)
- no., number (not no)
A recent dictionary, such as Webster’s New Collegiate Dictionary, is the best resource for determining if an abbreviation requires periods. See REFERENCES.
NOTE 3: Abbreviations with periods should be typed without spaces between letters and periods:
- e.g. (not e. g.)
- U.K. (not U. K.)
Use the same abbreviation for both singular and plural units of measurement.
When you abbreviate a unit of measurement, use the same symbol for both the singular and the plural forms:
- 6 lb and 1 lb
- 3 m and 1 m
- 20 ft and 1 ft
- 23.5 cm and 1.0 cm
If you spell out the abbreviated word, retain the plural when the number is greater than one:
- 15 kilometers and 1 kilometer
- 6.8 meters and 1 meter
Clarify an unfamiliar abbreviation by enclosing its unabbreviated form within parentheses following its first use in a document:
- The applicant had insurance through CHAMPUS (Civilian Health and Medical Program of the Uniformed Services).
- The alloy is hardened with 0.2 percent Np (neptunium). Adding Np before cooling alters the crystalline structure of manganese host alloys.
NOTE 1: Some writers and editors prefer to cite the unabbreviated form of the word or words before the abbreviation. We believe that this practice can inhibit, rather than enhance, the reader’s comprehension of the abbreviation:
- The applicant had insurance through the Civilian Health and Medical Program of the Uniformed Services (CHAMPUS).
- The alloy is hardened with 0.2 percent neptunium (Np). Adding Np before cooling alters the crystalline structure of manganese host alloys.
NOTE 2: Do not use an unfamiliar abbreviation unless you plan to use it more than once in the same document.
Do not abbreviate a unit of measurement unless it is used in conjunction with a number:
- Pipe diameters will be measured in inches.
- but
- Standard pipe diameter is 3 in.
- ______________
- The dimensions of the property were recorded in both meters and feet.
- but
- The property is 88 ft by 130 ft.
- The southern property line is 45.3 m.
Do not abbreviate a title unless it precedes a name:
- The cardiac research unit comprises five experienced doctors.
- but
- Our program director is Dr. Royce Smith.
Spell out abbreviations that begin a sentence (except for abbreviated words that, by convention, are never spelled out, like Mr. and Mrs.):
- Oxygen extraction will be accomplished at high temperatures.
- not
- O2 extraction will be accomplished at high temperatures.
- but
- Ms. Jean MacIntyre will be responsible for modifying our subsea sensors.
Spell out rather than abbreviate words that are connected to other words by hyphens:
- 6-foot gap (not 6-ft)
- 12-meter cargo bay (not 12-m)
- 3.25-inch pipe (not 3.25-in.)
NOTE: The spelled-out form is preferred. The abbreviated form (as in 6-ft) is common in some engineering documents, especially those with many numerical values. The hyphen is retained in the abbreviated form. See HYPHENS and FRACTIONS.
Do not abbreviate the names of months and days within normal text. Use the abbreviations in chronologies, notes, tables, and charts:
- The facilities modernization plan is due January 1985. (not Jan 1985 or 1/85)
Avoid the symbol form of abbreviations except in charts, graphs, illustrations, and other visual aids:
- 55 percent (not 55%)
- 15 ft (not 15’)
- 32.73 in. (not 32.73”)
Use a single period when an abbreviation ends a sentence:
- To head our laser redesign effort, we have hired the 1994 Nobel prize winner from the U.S.A. (not U.S.A..)
NOTE: If the clause or sentence ends with something other than a period, (e.g., comma, semicolon, colon, question mark, exclamation mark), then the other mark of punctuation follows the period at the end of the abbreviation:
- Have we hired the 1994 Nobel Prize winner from the U.S.A.?
- If you plan to arrive by 6 p.m., you will not need to guarantee your reservation.
List of Abbreviations
Following is a short list of many common abbreviations for words and common measurements. For more complete lists of abbreviations, refer to The Chicago Manual of Style and to Merriam-Webster’s Collegiate Dictionary. See REFERENCES.
In this listing, some abbreviations appear with periods, although the trend is to eliminate the periods (see rule 1). For example, Ph.D. appears with periods to assist writers and typists who wish to retain the periods, although many writers today prefer the increasingly more common PhD without periods.
In this listing, abbreviations printed without periods are ones that customarily appear without periods—for example, HF or log.
Abbreviations List
AA, Alcoholics Anonymous
A.B. or B.A., bachelor of arts
abbr., abbreviation
abs., absolute; absent; absence; abstract
acct., account; accountant
A.D. (anno Domini), in the year of the Lord
ADP, automated data processing
A.H. (anno Hegirae), in the year of the Hijra
a.k.a., also known as
A.M. (anno mundi), in the year of the world
A.M. or M.A., master of arts
a.m. (ante meridiem), before noon
A/P, accounts payable
app, application
approx., approximately
A/R, accounts receivable
Ave., avenue
a.w.l., absent with leave
a.w.o.l., absent without official leave
BAFO, best and final offer
B.C., before Christ
Bcc: blind courtesy copy
B.C.E., before the common era
bf., boldface
Bldg., building
B.Lit(t). or Lit(t).B., bachelor of literature
Blvd., boulevard
b.o., buyer’s option
BPS, basis points
B.S. or B.Sc., bachelor of science