I don't know if it's been in existence very long, but, reading a story on BBC, I've just learned the word 'fatberg'.
Eugh!
Makes you ill just thinking about it - an enormous mass (15 tonnes) of grease, disposable nappies / diapers and God knows what else clogged together in one huge lump. Apparently it's been discovered in a sewer under London. Had it been allowed to grow unchecked the consequences could have been disastrous.
Anyway, for me a new word - don't suppose it's in Chi yet?
MK