primary root

American  

noun

Botany.

1. the first root produced by a germinating seed, developing from the radicle of the embryo.

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primary root Scientific  

1. The first root of a plant, originating in the embryo. In gymnosperms, eudicotyledons, and magnoliids, the primary root develops into the taproot. In monocotyledons, the primary root disintegrates as the lateral roots develop into a system of fibrous roots.

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Etymology

Origin of primary root

First recorded in 1885–90

Example Sentences

From this primary root other roots develop, which are known as secondary roots.

From Dry-Farming : a System of Agriculture for Countries under a Low Rainfall by Widtsoe, John Andreas

G, a germinating seed, × 2. r, the primary root.

From Elements of Structural and Systematic Botany For High Schools and Elementary College Courses by Campbell, Douglas Houghton

These are exactly like the primary root from which they spring; there is no difference in structure or in machinery of growth. 

From Rustic Sounds and Other Studies in Literature and Natural History by Darwin, Francis, Sir

The single root of the commoner biennials is the primary root, or tap-root, which begins to thicken in the seedling.

From The Elements of Botany For Beginners and For Schools by Gray, Asa

In many Dicotyledons and most Monocotyledons, the primary root soon perishes, and its place is taken by adventitious roots developed from the stem.

From Encyclopaedia Britannica, 11th Edition, Volume 2, Part 1, Slice 1 by Various