Jeremy David Hanson, 34, was sentenced to a year in prison for threatening employees of Merriam-Webster after reading the definition for female.
"It is absolutely sickening that Merriam-Webster now tells blatant lies and promotes anti-science propaganda," he wrote in the comment section on the dictionary's website. "There is no such thing as 'gender identity.' The imbecile who wrote this entry should be hunted down and shot."
Hanson pleaded guilty in September to two counts of threatening communications to commit violence.
In addition to threatening employees of Merriam-Webster, he also admitted to threatening the President of the University of North Texas.
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He reportedly sent an email that was titled, "You ought to be shot in the head and have your offices set on fire for supporting child genital mutilation and transgenderism."
Prosecutors said Hanson also admitted to sending threatening communications to the Walt Disney Co., California Gov. Gavin Newsom, a New York rabbi and professors at Loyola Marymount University.
"Many of these threatening communications specified the race, gender, gender identity and/or sexual orientation of various persons," the Department of Justice said.
It's not uncommon for hateful comments to spread across the internet. If people believe comments they see are in violation of the law, they can file a report by calling the "End Hate Now" hotline at 1-83-END-H8-NOW.