Nephelococcygia

Nephelococcygia is one of these constructed words: it originally had a very specific meaning and is now put to another but connected use.

Nephelococcygia has it's origins in Aristophanese, the Greek playright. It means "Could Cuckoo Land", his utopian city in the clouds in one of his plays. As such it has always had a secondary meaning of being a dreamer, of not paying attention to reality. For the point of the play was that such utopias do not work nor do they exist.

Nephelococcygia also has a more modern meaning: the study of clouds. Or rather, cloud watching. While this is fun and all, it's slightly unfortunate that it has been described with this word with its connotations of being an otherworldly dreamer.