• (British) IPA: /ˈɒnˌsɛt/ attention en
• (America) IPA: /ˈɔnˌsɛt/ attention en
• (America, cot-caught) IPA: /ˈɑnˌsɛt/ attention en

onset (plural onsets)

1. (archaic) A rushing or setting upon; an attack; an assault; a storming; especially, the assault of an army.
   • c. 1596, William Shakespeare, “The Life and Death of King Iohn”, in Mr. William Shakespeares Comedies, Histories, & Tragedies: Published According to the True Originall Copies (First Folio), London: Printed by Isaac Iaggard, and Ed[ward] Blount, published 1623, OCLC 606515358 ↗, [Act II, scene i]:

     Heralds, from off our towers, we might behold
     From first to last, the onset and retire
     Of both your armies

   • ,

     Who on that day the word of onset gave.

2. (medicine) The initial phase of a disease or condition, in which symptoms first become apparent.

   the onset of schizophrenia

3. (phonology) The initial portion of a syllable, preceding the syllable nucleus.

   Antonyms: coda

   Coordinate terms: nucleus#English|nucleus, coda#English|coda

   holonyms en

4. (acoustics) The beginning of a musical note or other sound, in which the amplitude rises from zero to an initial peak.
5. A setting about; a beginning.

   Synonyms: start, beginning, Thesaurus:beginning

   the onset of puberty

   • 1625, Francis Bacon, Of Delays

     There is surely no greater wisdom than well to time the beginnings and onsets of things.

6. (obsolete) Anything set on, or added, as an ornament or as a useful appendage.
   • 1592, William Shakespeare , Titus Andronicus, Act 1, Scene 1

     And will with deeds requite thy gentleness:

     And, for an onset, Titus, to advance

     Thy name and honourable family,

     Lavinia will I make my empress.

• French: assaut, attaque
• Portuguese: investida
• Russian: ата́ка
• Spanish: arremetida

• Portuguese: anábase
• Spanish: aparición

• French: attaque
• German: Silbenansatz, Silbenanfang, Silbenanlaut
• Italian: attacco
• Portuguese: ataque
• Spanish: ataque

• French: attaque

onset (onsets, present participle onsetting; past and past participle onset)

1. (obsolete) To assault; to set upon.
2. (obsolete) To set about; to begin.