e.g. v. i.e. v. viz.

Clarity issues with this entry’s title notwithstanding, let’s see if we can elucidate when to use these abbreviations.

• e.g. stands for exempli gratia in Latin, and means ‘for example’.
• i.e. stands for id est in Latin, and means ‘in other words’.
• viz. stands for videlicet, a contraction of the Latin phrase vidēre licet, and means ‘namely’.

So, one would use e.g. to introduce one or more examples, i.e. to clarify or restate, and viz. to get more specific by either a) preceding a colon and a comprehensive list or b) following a general statement with a more detailed one.

Wikipedia’s list of Latin abbreviations

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