ENGLISH
REFERENCE

diurnal

adj.
C2 Proficiency US //daɪˈɝnəɫ// UK //dˈɪɜːnəl// di·ur·nal Archaic Botany
Definition

adj. relating to the daily cycle of day and night. In plants, it describes leaves that open during the day and close at night.

adj. relating to the daily cycle of day and night; specifically, in botany, describing leaves that open during the day and close at night. Often used in technical contexts to describe plant movements or animal activity patterns.


SIMPLE

The plant has diurnal leaves that open in the morning.

CONTEXTUAL

Many desert plants have diurnal habits, opening their flowers only during the cooler hours of the day to conserve moisture.

COMPLEX

The study focused on diurnal plant movements, specifically how certain species of legumes respond to changes in light intensity by adjusting the orientation of their leaflets.

Origin

From Latin diurnālis, from diēs (“day”). Doublet of journal.

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