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