What about
grok? To quote directly from
Stranger in a Strange Land:
"Take this word: 'grok.' Its literal meaning, one which I suspect goes back to the origin of the Martian race as thinking creatures--and which throws light on their whole 'map'--is easy. 'Grok' means 'to drink.'"
"Huh?" said Jubal. "Mike never says 'grok' when he's just talking about drinking. He--"
"Just a moment." Mahmoud spoke to Mike in Martian.
Mike looked faintly surprised. "'Grok' is drink."
"But Mike would have agreed," Mahmoud went on, "if I had named a hundred other English words, words which we all think of as different concepts, even antithetical concepts. 'Grok' means all of these. It means 'fear,' it means 'love,' it means 'hate'--proper hate, for by the Martian 'map' you cannot hate anything unless you grok it, understand it so thoroughly that you merge with it and it merges with you--then you can hate. By hating yourself. But this implies that you love it, too, and cherish it and would not have it otherwise. Then you can hate--and (I think) Martian hate is an emotion so black that the nearest human equivalent could only be called mild distaste."
There you have it. '
Grok' is its own antonym for hundreds of concepts, with the exception of one:
Understanding. 'Grok' fundamentally requires understanding, but is not a beefed up version of it, it is in fact an entirely new concept.
The Martian custom of 'grokking' an individual is at its heart a wake combined with ritual cannibalism. All the deceased individual's closest friends (water brothers) would get together and eat his body. In the process, they would pause occasionally to praise or condemn things about the person, actions he took, ideas he had, and whatnot. From that comes the ability of 'grok' to mean both 'love' and 'hate'.