hyponasty

American  

[hahy-puh-nas-tee] / ˈhaɪ pəˌnæs ti /

noun

Botany.

1. increased growth along the lower surface of a plant or plant part, causing it to bend upward.

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hyponasty British  

/ ˈhaɪpəˌnæstɪ /

noun

1. increased growth of the lower surface of a plant part, resulting in an upward bending of the part Compare epinasty

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Other Word Forms

• hyponastic adjective
• hyponastically adverb

Etymology

Origin of hyponasty

1870–75; hypo- + Greek nast ( ós ) pressed close, compact + -y ³

Example Sentences

As this upward movement occurred with plants kept in the dark and in whatever position the main peduncle was fastened, it could not have been caused by heliotropism or apogeotropism, but by hyponasty.

From The Power of Movement in Plants by Darwin, Charles

Afterwards they are carried upwards by apogeotropism in combination with hyponasty, and are thus enabled to scatter their seeds over a wider space.

From The Power of Movement in Plants by Darwin, Charles

The hooking depends chiefly, as far as we could ascertain, on the tip being affected by epinasty and geotropism; the lower and older parts continually straightening themselves through hyponasty and apogeotropism.

From The Power of Movement in Plants by Darwin, Charles

When the pod is nearly ripe, the upper part straightens itself and becomes erect; and this is due to hyponasty or apogeotropism, or both combined, and not to heliotropism, for it occurred in darkness.

From The Power of Movement in Plants by Darwin, Charles

These changes of position, which are due to epinasty or hyponasty, occur at certain periods of the life of the plant, and are independent of any external agency.

From The Power of Movement in Plants by Darwin, Charles