one-year-old

adj

"one-year-old" is a 10-letter English headword indexed on PlainSpell.

The verdict

“one-year-old” is uncommon English (outside the top frequency list), classed as an adjective. The kind of spelling people second-guess.

Unranked
below top-frequency English
12
letters

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - Having lived or existed for one year.

Key facts for one-year-old
PropertyValue
Headwordone-year-old
LanguageEnglish
Part of speechAdjective
Letters12
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “one-year-old” sits in English frequency

one-year-old falls outside the top-100,000 ranked English words, the long-tail zone of technical, archaic, or low-frequency vocabulary, exactly where readers second-guess spellings most.

Beyond rank #100,000. Source: FrequencyWords open word-frequency list.

Rare enough to double-check

one-year-old is uncommon English outside the top frequency list, classed as anadjective. Rarity is why readers land here mid-draft. Gloss: "Having lived or existed for one year.".

No misspelling variants are generated for one-year-old in our index, since its letter sequence doesn't invite the usual edit-distance slips. No confusable counterpart is on file for this word, since no other headword is close enough in sound or shape to pair with it.

Etymologically, the entry records: From one + year + old. The correct English form is one-year-old, spelled O-N-E---Y-E-A-R---O-L-D.

Definition

  1. 1
    Having lived or existed for one year.

Etymology

From one + year + old.

Synonyms

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

How do you spell "one-year-old"?
"one-year-old" is spelled O-N-E---Y-E-A-R---O-L-D.
What does "one-year-old" mean?
As an adjective, "one-year-old" means: Having lived or existed for one year.
What is the origin of the word "one-year-old"?
From one + year + old. See the full etymology section above for more details.
Is PlainSpell free to use?
Yes, PlainSpell is a completely free word reference. You can look up definitions, pronunciations, confusable pairs, homophones, and spelling corrections across 5 languages without any sign-up or subscription.

Using “one-year-old”

The practical upshot for anyone who landed here from a spell-check.

  • The one correct English spelling is O-N-E---Y-E-A-R---O-L-D - every other letter order is a misspelling in standard orthography.
  • 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.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list