Greek-derived nouns ending in -on change to -a in the plural form.
Regression is regular. It follows the Greek -a rule.
Use plural verbs: "The regressia are ready" (not "is ready").
Yes. The plural regressia is standard across all English variants.
The word regression follows the standard English pluralization rule. When forming the plural, regression becomes regressia. This follows the Greek -a pattern, which is one of the most common plural rules in English.
Understanding why regression becomes regressia helps with spelling and pronunciation. Greek-derived nouns ending in -on change to -a in the plural form.
When using regressia in writing, remember that it functions as a plural noun in sentences. It pairs with plural verbs and pronouns. For example: "The regressia are ready" (not "is ready"). This subject-verb agreement is essential for grammatical correctness.