Difference between Unexpected and Sudden

UNEXPECTED vs SUDDEN: NOUN

Happening without warning or in a short space of time
Happening without warning; unforeseen.
Happening or done without delay; hasty or immediate.
Characterized by sharp change in elevation; precipitous.
Happening without previous notice or with very brief notice; coming unexpectedly, or without the common preparation; immediate; instant; speedy.
Hastly prepared or employed; quick; rapid.
Hasty; violent; rash; precipitate.
Happening quickly and with little or no warning, snell.

Not expected; not looked for; unforeseen; sudden: often used substantively with the definite article: as, it is the unexpected that happens.

In zoology, abrupt; sharply defined from neighboring parts: as, a sudden antennal club; a sudden truncation.
Hasty; violent; rash; precipitate; passionate.
Hastily made, put in use, employed, prepared, etc.; quick; rapid.
Found or hit upon unexpectedly.
Happening without notice, instantly and unexpectedly; immediate; instant.
Suddenly; unexpectedly.
(idiom) (all of a sudden) Very quickly and unexpectedly; suddenly.

Unhoped, Out of the blue, Forced, Unthought, Upset, Unannounced, Unheralded, Unscheduled, Unsuspected, Sudden, Unplanned, Surprising, Unpredicted, Unanticipated, Unforeseen

Unplanned, Unanticipated, Surprising, Shock, Drastic, Rapid, Untimely, Precipitated, Dramatic, Precipitous, Explosive, Unforeseen, Sharp, Unexpected, Abrupt

Unhoped for, Unhoped, Forced, Unthought, Upset, Unannounced, Unheralded, Unscheduled, Unsuspected, Sudden, Unplanned, Surprising, Unpredicted, Unanticipated, Unforeseen

Unplanned, Unanticipated, Surprising, Shock, Drastic, Rapid, Untimely, Precipitated, Dramatic, Precipitous, Explosive, Unforeseen, Sharp, Unexpected, Abrupt

The expression contains an unexpected single quotation mark.
But, somehow for unexpected reasons, certain complicacy raises.
They can monitor the hallways for unexpected guests.
This unexpected situation must be fixed by programmers.
Polyhedral Model Gives the Universe An Unexpected Twist.
Unexpected ear disease in infants with cleft palate.
An unexpected love in a small, Southern town.
They find an unexpected, deadly new threat waiting.
The current experiment was designed to tease apart the impact of unexpected words from unexpected concepts.
The unexpected festivities it had planned for me like a lost job or an unexpected bill.

Sudden hearing loss with vertigo portends greater stroke risk than sudden hearing loss or vertigo alone.
Study aim To identify cases of sudden death in patients prescribed stimulant medications and Amoxetine to determine association between these and sudden death.
EDIT: It does give the impression of a sudden act of sudden reduction or going beneath though, rather than a steady ongoing process.
Sudden worsening of weakness may be triggered by infections, severe stress, surgery, or a reduction or sudden increase of prednisone.
The sudden appearance of the girl jolts her to a sudden stop.
The sudden discontinuation of the diamond trade was sudden economic downturn for many villagers.
If Sudden Death occurs in a Sudden Death game, this process is repeated.
This athlete is typically experiencing major lactic imminent hyperkalemia from sudden rhabdomyolysis that can complications or even sudden death.
How many words can you make out of sudden Another way to say Sudden Thought?
Flooded my chain nigga Then I Huncho the Range nigga All of a sudden, sudden, sudden All of a sudden.

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