embryo sac


: the female gametophyte of a seed plant consisting of a thin-walled sac within the nucellus that contains the egg nucleus and other nuclei which give rise to endosperm on fertilization

Word History

First Known Use

1844, in the meaning defined above

Time Traveler
The first known use of embryo sac was in 1844

Dictionary Entries Near embryo sac

Cite this Entry

“Embryo sac.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/embryo%20sac. Accessed 1 Dec. 2022.

Kids Definition

embryo sac


: the individual that produces female germ cells in the sexually reproducing generation of a seed plant and that consists of a thin-walled sac containing the egg nucleus and other nuclei which form tissue used for food upon fertilization

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