My hefty (dead-tree) Diccionari de la Llengua Catalana has only one word with Y – yperita (the y is pronounced ‘ee’) It doesn’t even have its own page, but is lumped together with Z.
So I could simply miss Y out, especially as I’ve already overshot the ‘official’ April A to Z Blogging 26-day schedule based on the English alphabet. But I’m also a bit obsessive, so… yperita is the chemical agent iperite, aka mustard gas: the French name ypérite comes from its usage near the town of Ypres in Belgium in the First World War. Interestingly, here Catalan keeps the French y- unlike English iperite, Spanish iperita, Italian iprite, although according to the (more up-to-date) online version of the Diccionari, iperita is also used.
As always, live and learn.
And if you’re wondering about more everyday items like yoga and yogurt, then remember – Catalans write them with initial I.