The plural form of ‘analysis’ is ‘analyses’. This change occurs because ‘analysis’ is a word of Greek origin, and in English, words derived from Greek often follow specific pluralization rules. In this case, the ‘-is’ ending changes to ‘-es’ to form the plural. For example, if you have one analysis, you might say, ‘This analysis is thorough.’ If you have multiple analyses, you would say, ‘These analyses are thorough.’