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sud·den

(sŭdn)

adj.

1. Happening without warning; unforeseen: a sudden storm.

2. Happening or done without delay; hasty or immediate: a sudden decision.

3. Characterized by sharp change in elevation; precipitous: a sudden drop in the ocean floor.

Idiom:

all of a sudden

Very quickly and unexpectedly; suddenly.

[Middle English sodain, from Old French, from Vulgar Latin *subitānus, from Latin subitāneus, from subitus, from past participle of subīre, to approach stealthily : sub-, secretly; see SUB- + īre, to go; see ei- in the Appendix of Indo-European roots.]

sudden·ly adv.

sudden·ness n.

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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