pronucleus

[ proh-noo-klee-uhs, -nyoo- ]

/ proʊˈnu kli əs, -ˈnyu- /

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noun, plural pro·nu·cle·i

[proh-noo-klee-ahy, -nyoo-]. /proʊˈnu kliˌaɪ, -ˈnyu-/. Cell Biology.

either of the gametic nuclei that unite in fertilization to form the nucleus of the zygote.

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Origin of pronucleus

From New Latin, dating back to 1875–80; see origin at pro-¹, nucleus

Words nearby pronucleus

pronounce, pronounced, pronouncement, pronto, pronuclear, pronucleus, pronuke, pronunciamento, pronunciation, pronunciation spelling, prony brake

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use pronucleus in a sentence

In Asterias glacialis the most favourable period for fecundation is about an hour after the formation of the female pronucleus.
The Works of Francis Maitland Balfour, Volume 1|Francis Maitland Balfour
In Echinus, on the other hand, where the polar bodies are formed in the ovary, the male pronucleus is always small.
The Works of Francis Maitland Balfour, Volume 1|Francis Maitland Balfour
When it finally unites with the female pronucleus it is equal in size to the latter.
The Works of Francis Maitland Balfour, Volume 1|Francis Maitland Balfour
The tail in the meantime vanishes, while the neck swells up and forms the male pronucleus.
The Works of Francis Maitland Balfour, Volume 1|Francis Maitland Balfour

Selenka, who has investigated the formation of the male pronucleus in Toxopneustes variegatus, differs in certain points from Fol.
The Works of Francis Maitland Balfour, Volume 1|Francis Maitland Balfour

British Dictionary definitions for pronucleus

pronucleus

/ (ˌprəʊˈnjuːklɪəs) /

noun plural -clei (-klɪˌaɪ)

the nucleus of a mature ovum or spermatozoan before fertilization

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for pronucleus

pronucleus

[ prō-nōō′klē-əs ]

One of two nuclei undergoing fusion in karyogamy.

The haploid nucleus of a sperm or egg before fusion of the nuclei in fertilization.