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