Onset Meaning
/ˈɒnˌsɛt/Definition, CEFR level B2, pronunciation, examples, and quiz.
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Definition
nounThe initial phase of a disease or condition, in which symptoms first become apparent.
nounThe initial portion of a syllable, preceding the syllable nucleus.
Sentence Examples
My dad's friend was diagnosed with early onset Alzheimer's disease.
The onset of malaria is marked by nausea, vomiting, fever, chills, and headache.
CEFR Practice Quiz
The sudden ____ of the storm forced the sailors to lower the sails immediately.
CEFR Practice Quiz (Alternate)
Doctors recommend early treatment at the ____ of symptoms to prevent the disease from progressing.
Word Origin & History
From on- + set. Compare Old English onsettan (“to impose; oppress, bear down”). For semantic parallels for the meaning to assault, compare cognate Russian насе́сть pf (naséstʹ), наседа́ть impf (nasedátʹ).
Literary Quotations & Historical Citations
"In mild cases of hypergonadism prior to puberty, the onset of physical and mood changes may not be abnormally early or significant enough to cause any psychological or long-term physical complications."
— 2018 June 25, James Roland, “What is Hypergonadism?”, in Healthline:
"Widely credited as an early pioneer of the modern railway, Shooter died peacefully of his own choosing in Switzerland on December 13, having bravely lived with the onset of motor neurone disease in the final years of his life."
— 2022 December 28, Paul Stephen, “Network News: Adrian Shooter CBE: rail industry mourns "a great man"”, in RAIL, number 973, page 6:
"The only regular sources for Sardinian *θ are Lat. ci̯ and ti̯, which are absent from Latin onsets. This means that the substantial number of words starting in *θ, discussed in § 3 – 7, cannot regularly continue a Latin form."
— 2025, Cid Swanenvleugel, The Pre-Roman Elements of the Sardinian Lexicon, page 390:
"There is surely no greater wisdom than well to time the beginnings and onsets of things."
— 1625, Francis [Bacon], “Of Delays”, in The Essayes […], 3rd edition, London: […] Iohn Haviland for Hanna Barret, →OCLC:
"Floods in northern India, mostly in the small state of Uttarakhand, have wrought disaster on an enormous scale. The early, intense onset of the monsoon on June 14th swelled rivers, washing away roads, bridges, hotels and even whole villages. Rock-filled torrents smashed vehicles and homes, burying victims under rubble and sludge."
— 2013 June 29, “High and wet”, in The Economist, volume 407, number 8842, page 28:
Explore More B2 Vocabulary Words
CEFR Practice Quiz
The sudden ____ of the storm forced the sailors to lower the sails immediately.
CEFR Practice Quiz (Alternate)
Doctors recommend early treatment at the ____ of symptoms to prevent the disease from progressing.