Insidious vs. Sudden

Insidiousadjective

Producing harm in a stealthy, often gradual, manner.

Insidiousadjective

Intending to entrap; alluring but harmful.

Insidiousadjective

(nonstandard) Treacherous.

Insidiousadjective

Lying in wait; watching an opportunity to insnare or entrap; deceitful; sly; treacherous; - said of persons; as, the insidious foe.

Insidiousadjective

Intended to entrap; characterized by treachery and deceit; as, insidious arts.

Insidiousadjective

Acting or proceeding unobserved or in a seemingly harmless manner, but slowly or eventually doing great damage; as, an insidious disease; an insidious plot.

Insidiousadjective

beguiling but harmful;

Insidiousadjective

intended to entrap

Insidiousadjective

working or spreading in a hidden and usually injurious way;

Insidiousadjective

proceeding in a gradual, subtle way, but with very harmful effects

Suddenadjective

Happening quickly and with little or no warning.

Suddenadjective

(obsolete) Hastily prepared or employed; quick; rapid.

Suddenadjective

(obsolete) Hasty; violent; rash; precipitate.

Suddenadverb

(poetic) Suddenly.

Suddennoun

(obsolete) An unexpected occurrence; a surprise.

Suddenadjective

Happening without previous notice or with very brief notice; coming unexpectedly, or without the common preparation; immediate; instant; speedy.

Suddenadjective

Hastly prepared or employed; quick; rapid.

Suddenadjective

Hasty; violent; rash; precipitate.

Suddenadverb

Suddenly; unexpectedly.

Suddennoun

An unexpected occurrence; a surprise.

Suddenadjective

happening without warning or in a short space of time;