otoconium

A Latinised adaptation (taking the form of a Latin second-declension neuter noun in the nominative case, as if from a Latin *ōtoconium) of the French otoconie (whence otocony, otokony), itself formed from the Ancient Greek οὖς, ὠτ- (oûs, ōt-, “ot-; ear”) + κονία (konía, “dust”).