UNILATERAL

u·ni·lat·er·al
(adj.) (of an action or decision) performed by or affecting only one person, group, or country involved in a particular situation, without the agreement of another or the others.

During the HH admin shitfest, one of the then-admins made a post to publicly protest the removal of one of the admins and appeal to the members of the group. In this post, said admin called this action "unilateral" and against the spirit of the group. The original post has since been removed.

As the controversy was discussed, the use of the word "unilateral" in HH skyrocketed because of this post. CdT members started to make fun of the repetition of the word by using it as often as possible, making it a bona fide meme.