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n. pl. pri·mor·di·a (-dē-ə)
An organ or a part in its most rudimentary form or stage of development.

[Latin prīmōrdium; see primordial.]


n, pl -dia (-dɪə)
(Biology) biology an organ or part in the earliest stage of development


(praɪˈmɔr di əm)

n., pl. -di•a (-di ə)
the first recognizable, histologically differentiated stage in the development of an organ.
[1665–75; < Latin prīmōrdium, in pl.: beginnings, elementary stage =prīm(us) first (see prime) + ōrd(īrī) to begin + -ium -ium1; compare exordium]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.primordium - an organ in its earliest stage of development; the foundation for subsequent development
organ - a fully differentiated structural and functional unit in an animal that is specialized for some particular function
References in periodicals archive ?
Anatomical sections of control and vehicle control mice fetuses showed normal left and right ventricles of brain, serous glands, intra-retinal space, lens, neural layer of retina, mandibular gland and cerebral aqua duct, hyaloid cavity, nasal septum and nasal cavity, primordium of frontal bone, follicle of vibrissae (Fig.
Delineation of the cerebellar primordium and early cell movements.
tuoliensis mycelium growth in 25degC, while induction and formation of fruit within 13-18degC Moreover, induction stress during environmental temperature of 0-4degC is a significant factor for primordium growth and development.
1]; covering at floral primordium with N at 34 kg [ha.
It has been shown that Wnt13 expressed from the cardiogenic mesoderm in mice and the frizzled-related protein 5, which acts as a Wnt inhibitor, regulate the development of liver primordium along with mutually stimulating and repressive effects (15).
2010) state that in most Cypereae species with distichously arranged glumes, the basal zone of the wings is fused with the rachilla, and such fusion zone grows as the rachilla rises, causing the wing tips to elongate along the internode and the main part of the glume and the flower primordium in its axil to displace.
In barley, the number of spikelets per spike at the awn primordium (AP) stage represents the maximum yield potential per spike.
This primordium gives rise to the gallbladder and the cystic duct.
Wood [53] defined primordium as a structure greater than 1 mm diameter composed of a dense hyphal mesh with a smooth surface and visibly distinct from strands or knots of hyphae.
The earliest thymic primordium could be identified at 6 wks.