suspended hyphen (-)
Definition - Ending a series of words with a hyphen to show that the words have a common suffix that will be shown by the last term in the series.

Example -

Pre- and post-war
25-, 35-, 45-, and 55-year-olds


1. Don't omit the hyphen on any of the preceding terms in the sequence.

First, second, and third-graders (bad)
First-, second-, and third-graders (good)

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