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