The definition of an underscore is an underline drawn under a word to emphasize it.(noun)
An underline underneath a word for emphasis is an example of an underscore.
Underscore is to emphasize something or to underline something.(verb)
When you emphasize the importance of following rules, this is an example of a time when you underscore the importance.
See underscore in Webster's New World College Dictionary
See underscore in American Heritage Dictionary 4
transitive verb un·der·scored, un·der·scor·ing, un·der·scores
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