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sudden

adj. · adv. · n.
US //ˈsədən// UK //sˈʌdən// sud·den
  1. 1 happening quickly (adj.)
    B1 Intermediate

    happening or done quickly and without warning.

    occurring, arriving, or performed unexpectedly and without prior notice.

    Example

    A sudden rain shower caught the hikers without their jackets.

    Example

    The sudden resignation of the chief executive left the board of directors scrambling to find a suitable interim replacement before the markets opened.
    Pitfall
    The car made a suddenly stop.
    The car made a sudden stop.

    Use the adjective 'sudden' to describe a noun like 'stop'. Use the adverb 'suddenly' to describe an action.

  2. 2 all of a sudden (adv.)
    B1 Intermediate

    used in the phrase 'all of a sudden' to mean 'suddenly'.

    functioning as an adverbial component, almost exclusively within the idiomatic prepositional phrase 'all of a sudden'.

    Example

    All of a sudden, the lights went out and the room was dark.

    Example

    The engine began to make a rhythmic clicking sound and then, all of a sudden, the entire vehicle shuddered and came to a halt.
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  1. 3 literary suddenly (adv.)
    C2 Proficiency Literary

    a poetic way to say 'suddenly'.

    used as a flat adverb in poetic or highly literary contexts to denote an abrupt occurrence.

    Example

    Sudden, the wind changed and the sails began to flap.

    Example

    Sudden there came a tapping, as of some one gently rapping at my chamber door.
  2. 4 an unexpected event (n.)
    C2 Proficiency Archaic

    a surprise or something that happens without warning.

    an unexpected or abrupt occurrence; now largely restricted to the fixed phrase 'on a sudden'.

    Example

    The news came upon them on a sudden.

    Example

    The arrival of the messenger on a sudden threw the entire household into a state of frantic preparation.
Origin

From Middle English sodeyn, sodain, from Anglo-Norman sodein, from Old French sodain, subdain (“immediate, sudden”), from Vulgar Latin *subitānus (“sudden”), from Latin subitāneus (“sudden”), from subitus (“sudden", literally, "that which has come stealthily”), originally the past participle of subīre (“to come or go stealthily”), from sub (“under”) + īre (“go”). Doublet of subitaneous. Displaced native Old English fǣrlīċ.

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