dot's shape of the italic abbreviation words

Question

I want to write

thief (pl. thieves)

Which is correct, the

\textbf{thief} (\textit{pl.} thieves)

or the

\textbf{thief} (\textit{pl}. thieves)

?

Answer 1

First, I don't think such questions would likely be dealt with in a style guide (most people being MS Word users, they do not reason in terms of "where do I put the brace/end-tag", especially since the difference between normal and italic periods isn't huge).

But as a matter of general typography, the abbreviation dot is a substitute for the letters that have been omitted, and hence belongs to the word, so I would go for italics. An illustration of this is the fact that you can write a comma after the abbreviation dot (because the dot is not punctuation, it is part of the word).

However, if you are using the abbreviation at the end of a sentence, you must omit the dot and keep only the period, so in that case it would not be italicised.

So, I would say:

Thief (\textit{pl.} thieves)
Call the \textit{vet.}, will you?
You should call the \textit{vet}.

EDIT in response to comments:

After re-checking over a dozen of books on typography and style, I have – as expected in my original answer – not found any specific reference to this particular question. I have clearly stated that this answer is my opinion precisely because I deduced it from the generally accepted rule (references below) according to which an abbreviation dot is not the same as a period (hence, the small punctuation symbols rule does not necessarily and automatically apply).

That the abbreviation dot is part of the abbreviated word (and is therefore not a period) is plainly stated in Lacroux's well-documented Orthotypographie (§§ 3.2.4 and 3.8), in French unfortunately – in this book, the abbreviation dots are, incidentally, typeset as I suggested. For TeX sources, both the \frenchspacing trick and the use of \@ are very well-known, and explained for instance by Will Robertson.

Once this is said, I think my argument follows logically (the dot belongs to the word), although anyone can indeed claim that this is only my opinion.

Answer 2

Bringhurst [chapter 3.5] recommends that you use the italic version of a small punctuation symbol on the boundary of italic/normal upright text - he calls it leaving the symbol in the background. I'd therefore write \textbf{thief} (\textit{pl.} thieves) because some typefaces may have italic versions of a full stop. When a small punctuation symbol is caught between boldface text and regular text, you should set it in the regular typeface: \textbf{pl}. thieves. See also chapter 2 of LaTeX and Friends:-).

Further references:

@book{Bringhurst,
  author    = {Bringhurst, Robert},
  title     = {The Elements of Typographic Style},
  shorttitle = {Elements of Typographic Style},
  version   = {3.2},
  publisher = {Hartley \&\ Marks},
  year      = {2008},
  isbn      = {0-988179-206-3}
}
@Book{vanDongen:2012,
  author    = {van~Dongen, M.\,R.\,C.},
  title     = {{\LaTeX} and Friends},
  publisher = {Springer},
  year      = {2012},
  isbn      = {978-3-642-23815-4},
  note      = {See \url{http://www.tug.org/books/reviews/tb102reviews-ltxfriends.html} for a review},
}

Answer 3

In addition to deciding whether the abbreviation mark (the period/full stop) should be set in italic or ordinary mode, there's (at least) one additional consideration you should contemplate:

• What to do about the fact that TeX will want to add a bit of additional whitespace after the period (unless \frenchspacing is in effect). Since the period is not a sentence-ending period, no extra space should be inserted after it. One method for achieving this is to insert an explicit space, \, immediately after the period. If there's a risk that the line might get broken after the pl., I'd insert a ~ (tilde) to make the space unbreakable.

Regarding your main question, i.e., whether to typeset the period following pl in italics or not, I'd follow common practice, viz., I'd set it in italics because it "belongs" to the "pl" that precedes it (and which you've decided should be set in italics).

Summing up, I'd create a macro, say, \nounentry:

\newcommand{\nounentry}[2]{\textbf{#1} (\emph{pl.}~#2)}

and use it as follows:

\nounentry{thief}{thieves}

Happy TeXing!