i.e. vs. e.g. Grammar Rules Explained image

Writers have used shortcuts and abbreviations for centuries. That’s not surprising, especially when you consider the manual effort involved in putting stylus, quill, brush, or pen to tablet, papyrus, vellum, silk, or paper.

Several Latin abbreviations have remained in use over the centuries. Unlike et al. and etc., which can be part of everyday prose, i.e. and e.g. are most often used today in scholarly or formal writing.

i.e. Means “That Is”

i.e. is an abbreviation of the Latin id est (“it is”often translated as “that is”). It restates, clarifies, or defines the preceding term.

  • Murphy is a particularly adorable member of the species Canis familiaris (i.e., a dog).
    Only dogs are members of this species.
  • Although he considered himself “vertically challenged” (i.e., short), Tim earned a spot on the school’s prestigious basketball team.
    “Vertically challenged” means “short.”
  • The coroner found the poison he suspected (i.e., arsenic) in the autopsy results.
    The coroner suspected one poison—arsenic—not lead, mercury, or cadmium.

e.g. Means “For Example”

e.g. means exempli gratia (for example), and indicates members of a larger category.

  • When packing for a trip, be sure to bring any toiletries you’ll need (e.g., toothbrush, razor, sunscreen).
    These are just a few examples of things you’ll need on your trip.
  • She was especially fond of Italian food (e.g., pizza, pasta, gelato).
    These are only a few types of Italian foods.

Both i.e. and e.g. use periods and are followed by commas.

  • They traveled to Hibernia (i.e., Ireland) and saw many famous sights (e.g., Dublin’s Temple Bar, Blarney Castle, Cliffs of Moher).

A Mnemonic Device to Remember the Difference

To keep these two terms straight, remember that the “i” in i.e. means “it” and the “e” in e.g. means “example.” To double-check, you can also substitute the abbreviation with its meaning.

For an absurdist view on the differences between i.e. and e.g., wander over to the Oatmeal and enjoy their comic take on the subject. You won’t learn any more than you did here, but you’re sure to smile.

Please note, however: In TCK style, i.e. and e.g. are used only in parentheses (i.e., like this) and not outside parentheses, e.g., like this.

Do you use these Latin abbreviations in your writing? Tell us in the comments below. 

Learn how more about using words correctly in these posts: