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