A manual for writers of research papers, theses, and dissertations, Ninth edition - Kate L. Turabian 2018

Special terms
Names, special terms, and titles of works
Style

Some special terms require use of italics, quotation marks, and capitalization.

22.2.1 Terms from Other Languages

Italicize isolated words and phrases in languages likely to be unfamiliar to readers of English, and capitalize them as in the original language. (If you are unfamiliar with the capitalization principles of a language, consult a reliable authority such as chapter 11 of The Chicago Manual of Style, 17th edition [2017].) For titles of works in languages other than English, see 22.3.1.

This leads to the idea of Übermensch and to the theory of the acte gratuit and surrealism.

Do not italicize terms from another language that are familiar enough to appear in a standard dictionary.

✵ de facto

✵ vis-à-vis

✵ pasha

✵ eros

Do not italicize proper names from other languages or personal titles that accompany them.

✵ Padre Pio

✵ the Académie Française

✵ the Puerto del Sol

If you define a non-English term, put the definition in parentheses or quotation marks, either following the term in the text or in a note.

The usual phrase was ena tuainu-iai, “I wanted to eat.”

According to Sartrean ontology, man is always de trop (in excess).

For longer quotations from another language, use roman type. (Italicize the quotation as a whole or any words within it only if they are italicized in the original.) Enclose the quotation in quotation marks within the text or use a block quotation following the principles in 25.2.

The confusion of le pragmatisme is traced to the supposed failure to distinguish “les propriétés de la valeur en général” from the incidental.

22.2.2 Words Defined as Terms

To emphasize key terms that you define, italicize them on their first use; thereafter use roman type. You can use quotation marks (called scare quotes) to alert readers that you are using a term in a nonstandard or ironic way. When overused, both techniques become less effective.

The two chief tactics of this group, obstructionism and misinformation, require careful analysis.

Government “efficiency” resulted in a huge deficit.

Italicize a term when you refer to it as a term.

The term critical mass is more often used metaphorically than literally.

How did she define the word existential?

but

A critical mass of students took existential philosophy.

Italicize letters referred to as letters, and present them in lowercase. Letters used to denote grades and to identify exemplars should be roman and capitalized. For plural forms of letters used in these ways, see 20.1.2.

Many of the place-names there begin with the letters h and k.

In her senior year, she received an A and six Bs.

Imagine a group of interconnected persons: A knows B, B knows C, and C knows D.