nyctitropic

American  

[nik-ti-trop-ik, -troh-pik] / ˌnɪk tɪˈtrɒp ɪk, -ˈtroʊ pɪk /

adjective

Botany.

1. tending to assume at or just before nightfall positions unlike those maintained during the day, as the leaves or flowers of certain plants.

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Other Word Forms

• nyctitropism noun

Etymology

Origin of nyctitropic

First recorded in 1875–80; nycti- + -tropic

Example Sentences

Associated word: nyctitropic. sleepwalker, n. somnambulist, noctambulist, somnambulator, somnambule. sleepwalking, n. somnambulism, somnambulation, somnambulance, noctambulism, noctambulation.

From Project Gutenberg

Trifolium resupinatum: circumnutation and nyctitropic movements of the terminal leaflet during 24 hours.

From Project Gutenberg

Passiflora gracilis: circumnutation and nyctitropic movement of leaf, traced on vertical glass, from 8.20 A.M.

From Project Gutenberg

The fact of the leaves of several plants not sleeping unless they have been well illuminated during the day, made us for a time doubt whether the protection of their upper surfaces from radiation was in all cases the final cause of their well-pronounced nyctitropic movements.

From Project Gutenberg

Although we can see how the slight periodical movements of leaves in a vertical plane could be easily converted into the greater yet simple nyctitropic movements, we do not at present know by what graduated steps the more complex movements, effected by the torsion of the pulvini, have been acquired.

From Project Gutenberg