[noo-sel-uh s, nyoo-]
- the central cellular mass of the body of the ovule, containing the embryo sac.
Origin of nucellus
1880–85; < New Latin, equivalent to Latin nuc- (stem of nux) nut + -ella -elle
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for nucellus
The nucellus is a cellular tissue enveloping one large cell, the embryo-sac or macrospore.
The Insemineae include forms in which the nucellus is not developed, and therefore there can be no seed.
In Araucaria and Saxegothaea the nucellus itself projects beyond the open micropyle and receives the pollen-grains direct.
The vessels of the cord are prolonged to the base of the nucellus n by means of the raphe r.
The base of the nucellus is indicated by the chalaza ch, while the apex is at the micropyle m.
- the central part of a plant ovule containing the embryo sac
C19: New Latin, from Latin nucella, from nux nut
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
- The megasporangium of a seed-bearing plant, located in the ovule. In angiosperms, it is the central portion of the ovule in which the embryo sac develops. In some cases of apomixis (production of seeds without fertilization), cells of the nucellus develop into an embryo.
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