I always thought was pronounced "galuta".
However I just noticed in my sidur today in יקום פורקן , the words there are "reshei galvata".
Is that just the plural of "galuta"? Or have I been pronouncing it wrong all along?
When referring to a singular galus, it is pronounced גָּלוּתָא; see e.g. Daniel 2:25: ״מִן בְּנֵי גָלוּתָא״.
When referring to exiles in the plural, it is pronounced גַּלְוָתָא. (Compare Daniel 6:8: ״לְגֹב אַרְיָוָתָא״)