• WordNet 3.6
    • n onset (military) an offensive against an enemy (using weapons) "the attack began at dawn"
    • n onset the beginning or early stages "the onset of pneumonia"
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Webster's Revised Unabridged Dictionary
    • Onset A rushing or setting upon; an attack; an assault; a storming; especially, the assault of an army. "The onset and retire
      Of both your armies."
      "Who on that day the word of onset gave."
    • Onset A setting about; a beginning; -- used especially of diseases or pathological symptoms. "There is surely no greater wisdom than well to time the beginnings and onsets of things."
    • Onset Anything set on, or added, as an ornament or as a useful appendage.
    • Onset To assault; to set upon.
    • Onset To set about; to begin.
    • ***
Century Dictionary and Cyclopedia
    • n onset A rushing or setting upon; attack; assault; especially, the assault of an army or body of troops upon an enemy or a fort, or the order for such an assault.
    • n onset Start; beginning; initial step or stage; outset.
    • n onset An attack of any kind: as, the impetuous onset of grief.
    • n onset Something set on or added by way of ornament. Synonyms Attack, Charge, Onset, Assault, Onslaught. Attack is the general word; the rest are arranged according to the degree of violence implied. Charge is a military word: as, “The Charge of the Light Brigade.” Onset generally applies to a collective movement; assault and onslaught, may indicate the act of many or of one. An onslaught is rough and sudden, without method or persistence.
    • onset To assault; begin.
    • ***
Chambers's Twentieth Century Dictionary
    • n Onset on′set violent attack: assault: storming.
    • ***


  • Edward G. Bulwer-Lytton
    “Refuse to be ill. Never tell people you are ill; never own it to yourself. Illness is one of those things which a man should resist on principle at the onset.”


Webster's Revised Unabridged Dictionary
On, + set,
Chambers's Twentieth Century Dictionary
On and set.


In literature:

It is always most intense and most rapid in its onset when death is preceded by active muscular exertion.
"Disease and Its Causes" by William Thomas Councilman
The onset was now preparing; everyone as I have described before kept knocking stones together, and Eefow quitted me.
"A Voyage to the South Sea" by William Bligh
And that mighty array (of the Pandavas) wavered at the onset of that hero.
"The Mahabharata of Krishna-Dwaipayana Vyasa, Volume 2"
In the first onset, they broke their lances and then, drawing sword, they fought blade to blade.
"Stories from Le Morte D'Arthur and the Mabinogion" by Beatrice Clay
Beyond the bellowing onset of base war, Their latest wearer wendeth!
"Punch, or the London Charivari, Vol. 103, October 22, 1892" by Various
They made a sudden onset, and bore back the small band of white men.
"Gascoyne, The Sandal Wood Trader" by R. M. Ballantyne
He had very nearly broken down at the onset, but, as the reader will have observed, had recovered himself.
"The Claverings" by Anthony Trollope
At this last onset the defenders were almost overwhelmed, repeated volleys seeming only to inflame the fierce warriors.
"Round the World in Seven Days" by Herbert Strang
The onset of the French was irresistible.
"Notable Events of the Nineteenth Century" by Various
When one has but a single weak place to defend, one protects it against an onset.
"The Original Fables of La Fontaine" by Jean de la Fontaine

In poetry:

He heeded not the fierce onsets
From bristling fields of bayonets;
He heeded not
The thunder-tread of warring steeds,
But holds his men of daring deeds
Right on the spot.
"Stonewall Jackson" by Albery Allson Whitman
But every arm is half unnerved—
Each rider in the onset swerved—
Rein half-tightened, lance half-thrust,
A palsy on the battle's lust,
For still each beating breast about
Is wound the web: "I doubt! I doubt!"
"The Battle-Day, Or, The Lost Army" by Ernest Jones
Wyandot's chieftain grave,
Young and lithe, hold and brave,
Stood by Tecumthe, waiting the beginning of the fray;
Tecumthe silence broke,
And thus to him he spoke,
"My brother from this onset I'll never come away.
"Tecumthe" by Nora Pembroke
The proud king heading the host on his red roan charger.
Dust. On a thicket of spears glares the Syrian sun,
The Saracens swarm to the onset, larger aye larger
Loom their fierce cohorts, they shout as the day were won.
"The Sleep of Sigismund" by Jean Ingelow
There, when the cloud
Eased its dark breast in thunder, and the light
Ran forth, their hearts recall the loud
Hoarse onset roar, the flashing of the fight;
Those other clouds piled-up in white array
Whence deadlier lightnings play.
"At Hursley In Marden" by Francis Turner Palgrave
"Bear the banner I broidered
Straight, straight to the core of the conflict; at sunset
My maidens shall croon the old songs of our sireland,
And our prayers shall ascend for the brave in the onset–
The faithful and noble who struggle for Ireland!
"Sir Turlough" by Anna Johnston MacManus

In news:

Responding to the onset of colder winter temperatures in December, Westside Christian High School students teamed up with Beaverton-based non-profit organization Ncompass to provide warm sleeping bags for Portland's homeless.
Jupiter rises just before midnight, and Venus is well up by the onset of dawn twilight.
The summer annual flowers are beginning to fade with the onset of cooler weather.
Teena Adler can feel the onset of her manic episodes: that swift, dramatic toggle from normalcy to paranoia.
A final burst of silly season before onset of thrilling season.
Frank ( Buddy ) Allen of Buda, TX flew to Jesus on Dec 5, at the young age of 63, due to a sudden onset of liver complications for which he suffered only a month.
(Kevin Clark/The Washington Post) Cooling fruit: That's what we need in this onset of dog days.
Passion for hoops helps Mark Houppert cope with early-onset Parkinson's.
A late spring, or a severe summer drought can delay the onset of fall color by a few weeks.
A 54-year-old man sought medical attention due to the acute onset of a painful scrotal rash.
Early onset, embarrassing symptoms and life-changing surgeries: seven men and women with Crohn 's disease speak.
Pregnancy snoring onset may signal hypertension.
Onset of Bourne, Mass.
Pat Summitt has early onset dementia.
FDA Approves Genzyme Product for Late- Onset Pompe Disease.

In science:

This burst has a very strong oscillation begining ≤ 0.05 s after onset (see Figure 1, left panel).
Oscillations During Thermonuclear X-ray Bursts
We also discuss the breakdown of such regime at very large energies, and the onset of the non-perturbative Pomeron behaviour.
Diffusion corrections to the hard pomeron
There is not a strong L dependence for the onset of the molten globule domain.
Coil-Globule Transition for Regular, Random and Specially Designed Copolymers: Monte Carlo Simulation and Self-Consistent Field Theory
Here, we are mainly interesting in chaotic solutions near the onset of symplectic chaos, where the phase space of the map has a dimension higher than two.
Random Wandering Around Homoclinic-like Manifolds in Symplectic Map Chain
This effect seems to be due to the onset of a saturation of both the PMTs above ≈ 20 PE per pixel and (some of ) the ADC electronics, in account of the high PMT gain used.
Experimental study of a proximity focusing Cherenkov counter prototype for the AMS experiment