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di·ur·nal

(dī-ûrnəl)

adj.

1. Relating to or occurring in a 24-hour period; daily.

2. Occurring or active during the daytime rather than at night: diurnal animals.

3. Botany Opening during daylight hours and closing at night.

1. A book containing all the offices for the daily canonical hours of prayer except matins.

2. Archaic

a. A diary or journal.

b. A daily newspaper.

[Middle English, from Late Latin diurnālis, from Latin diurnus, from diēs, day; see dyeu- in the Appendix of Indo-European roots.]

di·urnal·ly adv.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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