Hate, or hatred, was a negative emotion considered to be the opposite of love. This emotion was triggered by a persistent feeling of being threatened, disgust, anger, or irritation towards the hostility. It will be even more intense and deeper than anger, with it becoming in some cases a revengeful grudge. The cause of the hate will become deep-rooted and will last a while. An individual filled up with hate impulses will develop even more intense emotions such as revenge and strong disgust.
In Vok'sha mythology, hate was a beast that lived inside the stomach. (VOY: "Heroes and Demons")
Armus was the personification of hate. (TNG: "Skin Of Evil")
The Talosians were unable to read through "primitive emotions" such as hate. (TOS: "The Cage")
When the Romulan commander Sela ordered Spock to read a false statement that she had prepared for him, he told her that he would not. She threatened that if he did not, he and those with him would die, but he answered that it was logical that she would kill them regardless of what he did, so he would not cooperate. Aggravated, she declared that she hated Vulcans, that she hated their logic and arrogance. (TNG: "Unification II")
Major Kira Nerys hated holosuites. (DS9: "Meridian")
After first gaining emotions via his emotion chip, Data sampled a new beverage from Forcas III served by Guinan in Ten Forward of the USS Enterprise-D. Upon tasting it, he was confused by his reaction before realizing that he hated it, but was delighted by the unexpected experience and asked for more. (Star Trek Generations)