when Both partners reach climax simultaneously while making love

Briefly, "the realization that each random passerby is living a life as vivid and complex as your own." Originally from the Dictionary of Obscure Sorrows, which has a lot more beautiful neologism definitions like this you might enjoy.

The intense feeling of pleasure a communist experiences when occupying themselves with all matters communism, such as (marching) music, Marxist literature, Commie gatherings, or the victory of communism in (the Vietnam) war.