Use hyphens to link
Also use hyphens for the following purposes:
In typewritten documents, a single hyphen repesents the typographical en dash, a dash the width of the letter n. Conventions for using hyphens differ from discipline to discipline. When in doubt about whether to hyphenate a word, check the appropriate style guide.
Use hyphens to connect certain prefixes to nouns. In most scientific and technical styles, the following prefixes are usually followed by a hyphen:
However, scientific and technical writing styles omit the hyphen between most prefixes, especially prefixes that are not words themselves. The following list of prefixes that normally are not followed by a hyphen is adapted from Scientific Style and Format by the Council of Biology Editors:
When adding a prefix to a noun forms a homograph (a word with two meanings), use a hyphen for clarity.
Use hyphens to connect numbers or letters used as prefixes to a noun.
Use a hyphen to connect any prefix to a capitalized noun.
In most cases, do not place a hyphen before a suffix. In most scientific and technical styles, however, the following suffixes are preceded by a hyphen.
Use a hyphen to link compound nouns, especially when the lack of a hyphen would change the meaning of the term.
[The first term is a unit of measurement, not of time; the second pair of words, on the other hand, may indicate a year that is not heavy.]
Use a hyphen to connect compound modifiers to promote clarity and prevent ambiguity.
laser-alignment process [compound modifier + noun]
laser alignment [modifier + noun]
the two-tube combiner
wire-grid aperture cap [aperture cap for a wire grid]
wire grid-aperture cap [a wire cap for a grid aperture]
wire-grid level adjustment
wire grid-level adjustment
heavy-water cavity [a cavity for heavy water]
heavy water cavity [a water cavity that is heavy]
Use a hyphen to join spelled-out numbers from 21 through 99 and spelled-out fractions.
twenty-one moving parts
the thirty-third experiment
four-fifths of the subjects
In general, avoid dividing words. However, use hyphens to split words at the end of a line to prevent large spaces between words in justified text and noticeably uneven margins in unjustified text. The following guidelines for dividing words are adapted from the Chicago Manual of Style and the NASA Style Guide and the Council of Biology Editors' manual.
Use hyphens to stand for through or to, especially in bibliographies and reference lists. (However, when a number, letter, or date is preceded by the word from, use the word to instead of a hyphen.)
from 1901 to 1911
Use a hyphen in the following circumstances:
If all unit modifiers in a series end with the same term, the term does not have to be repeated each time; for brevity you may suspend the hyphens and use the modified term only at the end of the series.
The first-order, second-order, and third-order equations have all been
The first-, second-, and third-order equations have all been solved.
2- and 3-phase controllers