onset
on·set/ˈɒnˌsɛt/noun
onset is spelled O-N-S-E-T: 5 letters and 2 syllables (on·set). It appears 5.2 times per million words in written English, the 10,843rd most frequent word form (wordfreq, 2021 data). As a noun, onset means “The initial phase of a disease or condition, in which symptoms first become apparent” (English Wiktionary, September 2026). The plural of onset is onsets.
How many letters and syllables are in onset?
| Letters | 5: O-N-S-E-T |
|---|---|
| Syllables | 2: on·set |
| In writing | 5.2 times per million words; the 10,843rd most frequent word form |
| Wrong spellings searched | none measured in search |
| Same letters |
Sources: letters and syllables from the English Wiktionary's hyphenation or pronunciation; written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media); rhymes and same-letter words are computed by PlainSpell from its own word list.
How common is onset?
Onset appears 5.2 times per million words in written English, the 10,843rd most frequent word form in the list.
Source: written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
How do you pronounce onset?
- UK /ˈɒnˌsɛt/
- /ˈɔnˌsɛt/
- /ˈɑnˌsɛt/
Onset has 2 syllables, split on·set in writing.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Recordings: LL-Q1860_(eng)-Vealhurl-onset.wav, LL-Q1860_(eng)-Rho9998-onset.wav, Wikimedia Commons (author and licence on each file's page).
What rhymes with onset?
No other word on PlainSpell ends in the same sounds as onset (/ɒnsɛt/).
Spelled with the same letters in another order: notes, stone, seton, steno.
Computed by PlainSpell from the pronunciations in the English Wiktionary (dump of September 2, 2026): a rhyme shares every sound from the last stressed vowel to the end; ordered by written frequency (wordfreq 3.1).
Forms of onset
- onsets plural, present, singular, he/she/it
- onsetting participle, present
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
What does onset mean?
The meanings the English Wiktionary records, quoted as written there (source below).
noun
- 1
The initial phase of a disease or condition, in which symptoms first become apparent.
the onset of schizophrenia
- 2
The initial portion of a syllable, preceding the syllable nucleus.
- 3
The beginning of a musical note or other sound, in which the amplitude rises from zero to an initial peak.
- 4
A setting about; a beginning.
the onset of puberty
- 5
obsoleteAnything added, such as an ornament or as a useful appendage.
- 6
archaicAn attack; an assault especially of an army.
verb
- 1
obsoleteTo assault; to set upon.
- 2
obsoleteTo set about; to begin.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
Onset in Spanish, French, German and Portuguese
| Language | Words |
|---|---|
| French | assaut, attaque , début, apparition |
| German | Angriff, Ansturm , Anzeichen , Silbenansatz, Silbenanfang, Silbenanlaut |
| Portuguese | investida , anábase , ataque |
| Spanish | arremetida , principio , ataque silábico, inicio silábico |
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Translations are Wiktionary's, by sense; a linked word has its own PlainSpell page.
Where does onset come from?
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).
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).