ab initio
/ˌæb ɪˈnɪʃ.i.oʊ/
"ab-initio" is a 8-letter English headword indexed on PlainSpell.
The verdict
“ab initio” is outside the top-ranked English vocabulary, used as an adverb - the kind of word writers most often double-check.
- Unranked
- below top-frequency English
- 9
- letters
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - From the time when a law, legal right or decree, contract, ownership interest, partnership (etc.) comes into force.
| Property | Value |
|---|---|
| Headword | ab initio |
| Language | English |
| Part of speech | Adverb |
| IPA | /ˌæb ɪˈnɪʃ.i.oʊ/ |
| Letters | 9 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Where “ab initio” sits in English frequency
Spelling & Dictionary Insight
The English entry for ab initio is 9 letters long, classified as an adverb, and transcribed in the International Phonetic Alphabet as /ˌæb ɪˈnɪʃ.i.oʊ/. It sits outside the most-frequent rank tiers, which is often why uncommon words generate more spelling variants per reader. Wiktionary records 3 distinct senses for this headword, so context determines which meaning a reader should apply.
The misspelling generator found no plausible variants for ab initio, since its letter sequence doesn't invite the usual edit-distance slips. Our dataset records no confusable match here, which typically means the spelling is too distinctive to be mistaken for another word.
Etymologically, the entry records: From Latin ab (“from”) + initiō, ablative singular of initium (“beginning”). The correct English form is ab initio, spelled A-B- -I-N-I-T-I-O.
Definition
- 1From the time when a law, legal right or decree, contract, ownership interest, partnership (etc.) comes into force.
- 2Calculated from first principles, i.e. from basic laws without any further additional assumptions.
- 3Taken with no prior qualifications.
Etymology
From Latin ab (“from”) + initiō, ablative singular of initium (“beginning”).
This word in other languages
Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA). See the methodology for how each field is sourced and updated.
Frequently Asked Questions
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Using “ab initio”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is A-B- -I-N-I-T-I-O - every other letter order is a misspelling in standard orthography.
- Say it as /ˌæb ɪˈnɪʃ.i.oʊ/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
- Browse more English words and confusable pairs in the same reference. English words
Data Source
Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Word ordering uses an open word-frequency list; misspelling variants are generated by edit-distance from the correct headword.