phrase
Latin
i.e. (id est)
lit. “that is”
'That is to say' — used to restate something more precisely or clarify what was just said.
Origin
From id est ('that is'). The abbreviation has been standard in English writing since the 17th century. Distinct from e.g. (exempli gratia, 'for example') though they are constantly confused — i.e. introduces a restatement, e.g. introduces an example.
Modern usage
Everywhere in writing — academic, professional, casual. Style guides (Chicago, AP) prefer a comma after it; British style often omits the comma. 'i.e.' vs. 'e.g.' is one of the most-corrected mistakes in pedantic copy editing.
In the wild
Bring something easy to share, i.e., not a five-course meal.— common usage
Tags
clarification
abbreviation
writing