This question has already been asked and answered on this site, more than once. The answer is nuclei.
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The noun form of nuclear is nucleus, meaning the central core of an atom around which the electrons buzz.
The plural (from Latin) is nuclei. The plural possessive is nuclei's.
Nuclei is the plural of nucleus. It's already in plural form.
nuclei
Nuclei
The plural form of nucleus is nuclei.
nucleoli
Nuclei
The singular possessive form is heart's; the plural possessive form is hearts'.
The plural form is homes; the plural possessive is homes'.
The plural of rose is roses. The plural possessive is roses'.
The plural possessive is regions'.
The plural possessive is governesses'.
Singular possessive: secretary's Plural: secretaries Plural possessive: secretaries'
The plural is relatives. The plural possessive is relatives'.
The plural is lads. The plural possessive is lads'.
The plural form is Mexicans. The plural possessive is Mexicans'.
The plural form is suffixes. The plural possessive is suffixes'.
The plural possessive of stepsister is stepsisters'.
The plural form is inches. The plural possessive is inches'.
The plural form is echoes. The plural possessive is echoes'.
Coaster's is singular possessive. The plural is coasters, the plural possessive is coasters'.
The plural possessive is pals'.
The plural possessive of bandit is bandits'.
Studies' is the plural possessive of study.