pronucleus vs karyon

pronucleus and karyon both are nouns.

Word	Noun	Adjective	Verb	Adverb
pronucleus	Yes	No	No	No
karyon	Yes	No	No	No

As nouns, karyon is a hypernym of pronucleus; that is, karyon is a word with a broader meaning than pronucleus:

pronucleus: the nucleus of the ovum or sperm after fertilization but before they fuse to form the nucleus of the zygote
karyon: a part of the cell containing DNA and RNA and responsible for growth and reproduction

Other hypernyms of pronucleus include cell nucleus, nucleus.

pronucleus (noun)	karyon (noun)
the nucleus of the ovum or sperm after fertilization but before they fuse to form the nucleus of the zygote	a part of the cell containing DNA and RNA and responsible for growth and reproduction