The word "yttro" is a unique and rare term in the English language. Its spelling might seem strange, but it is pronounced as [ˈɪtroʊ]. The "y" in "yttro" represents the "i" sound, and the double "t" serves to elongate the following vowel. This word originates from the rare earth element yttrium, and it is most commonly found in scientific or technical writing. While the spelling might cause some confusion, knowing its phonetic transcription can assist in proper pronunciation.
A prefix signifying that the compound contains yttria as a constituent.
Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874.