onerous
/ˈɑnəɹəs/adjective
onerous is spelled O-N-E-R-O-U-S: 7 letters and 3 syllables. It appears about once in every 1 million words in written English, the 31,974th most frequent word form (wordfreq, 2021 data). As an adjective, onerous means “Imposing or constituting a physical, mental, or figurative load which can be borne only with effort; burdensome” (English Wiktionary, September 2026).
How many letters and syllables are in onerous?
| Letters | 7: O-N-E-R-O-U-S |
|---|---|
| Syllables | 3 (from its American pronunciation) |
| In writing | about once in every 1 million words; the 31,974th most frequent word form |
| Wrong spellings searched | none measured in search |
| Rhymes with |
Sources: letters and syllables from the English Wiktionary's hyphenation or pronunciation and the CMU Pronouncing Dictionary; 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 onerous?
Onerous appears about once in every 1 million words in written English, the 31,974th 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 onerous?
- UK /ˈɒnəɹəs/
- UK /ˈəʊnəɹəs/
- US /ˈɑnəɹəs/
Onerous has 3 syllables (counted from its American pronunciation in the CMU Pronouncing Dictionary).
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Recordings: LL-Q1860_(eng)-Vealhurl-onerous.wav, LL-Q1860_(eng)-Vealhurl-onerous2.wav, Wikimedia Commons (author and licence on each file's page).
What rhymes with onerous?
One word on PlainSpell end in the same sounds as onerous from its last stressed vowel (/ɑnəɹəs/):
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 onerous
- more onerous comparative
- most onerous superlative
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
What does onerous mean?
The meanings the English Wiktionary records, quoted as written there (source below).
adjective
- 1
Imposing or constituting a physical, mental, or figurative load which can be borne only with effort; burdensome.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
Onerous in Spanish, French, German and Portuguese
In the sense burdensome:
| Language | Words |
|---|---|
| French | onéreux, pénible, lourd |
| German | beschwerlich, drückend, lästig, mühsam |
| Portuguese | oneroso |
| Spanish | oneroso |
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 onerous come from?
Inherited from Middle English onerous, borrowed from Middle French onereux, from Old French onereus, a learned borrowing from Latin onerosus, from onus (“burden”) + -ōsus. Compare exonerate.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).