Gentium Book

Gentium Book is a serif typeface designed for readable text in Latin, Cyrillic, and Greek scripts. The family is intended for multilingual publishing and includes characters and symbols useful for linguistics and literacy work.

• The supplied font files cover regular, italic, medium, semibold, and bold styles, with italic files for regular, medium, semibold, and bold.
• The official site describes support for Latin, Cyrillic, and Greek, including diacritics and OpenType features such as small caps and diacritic positioning.
• Its design emphasizes readability, with relatively open letterforms and a compact overall appearance.

Install it with brew install --cask font-gentium-book. This cask installs the eight font files into ~/Library/Fonts. After installation, select Gentium Book in the font menu of a compatible application to use it; this installs a font, not a standalone app.

The installed files are the styles listed above; the cask does not install every possible Gentium family variant. Font support for scripts and features does not guarantee coverage of every character or behavior in every application.

Sources: Gentium official site