online

/ˈɒnlaɪn/

//ˈɒnlaɪn// adj

By · According to Wiktionary data (CC BY-SA) ·

"online" is a 6-letter English headword indexed on PlainSpell.

The verdict

“online” is in the everyday core of English, ranked #659 in English word frequency and used as an adjective.

#659
frequency rank, English
6
letters
8
tracked misspellings
7
confusable pairs

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - Of a system: connected (generally electrically) to a larger network.

Visual similarity to commonly confused words

How many letter changes separate each confused pair (Levenshtein distance, normalized).

online vs onsite
67% similar
online vs onside
67% similar
online vs outline
71% similar

Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).

Key facts for online
PropertyValue
Headwordonline
LanguageEnglish
Part of speechAdjective
IPA/ˈɒnlaɪn/
Letters6
Frequency rank#659
Misspellings tracked8
Confusable pairs7
SourceWiktionary (kaikki.org)

Where “online” sits in English frequency

Every-word frequency runs from the handful of words we use constantly (left) to the long tail used once in a blue moon (right). online lands here:

#1#100#1K#10K#100K
← used constantlyrarely used →

Scale is logarithmic (each tick is 10× rarer). Source: FrequencyWords open word-frequency list.

Spelling & Dictionary Insight

The English entry for online is 6 letters long, classified as an adjective, and transcribed in the International Phonetic Alphabet as /ˈɒnlaɪn/. Corpus data places it at rank #659 in overall English word frequency, putting it firmly in the everyday core of the language. Wiktionary records 7 distinct senses for this headword, so context determines which meaning a reader should apply.

Our generated misspelling index lists 8 likely wrong-spelling variants for online, with forms such as "noline", "olnine", and "onilne". Every one of these variants traces to a single-character edit -- an added or dropped letter, a swapped consonant, or a vowel swap -- the kind of slip a spell-checker is built to catch. It also participates in 7 confusable-pair relationships, "onsite", "onside", "outline", and more, since the words sound or look close enough that writers reach for the wrong one mid-sentence.

Etymologically, the entry records: 1950, from on + line. The correct English form is online, spelled O-N-L-I-N-E.

Definition

  1. 1
    Of a system: connected (generally electrically) to a larger network.
  2. 2
    Of a system: connected (generally electrically) to a larger network.
  3. 3
    Available over, or delivered from, the Internet.
  4. 4
    Connected to the Internet.
  5. 5
    Available on a computer system, even if not networked.
  6. 6
    Of a system: active, particularly building facilities (such as power) or a factory or power plant.
  7. 7
    Immersed in Internet culture. (Usually modified by an intensifier such as extremely or terminally)

Etymology

1950, from on + line.

Antonyms

offlinehardcopybrick and mortarliving under a rock

This word in other languages

internauta(Español)en ligne(Français)online(Deutsch)em linha(Português)

Common misspellings

Also misspelled as: noline,olnine,onilne,onlien,onlinne,onlline,onlnie,onnline

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of online - counted as single-character edits (an insertion, a deletion, or a substituted letter). The larger the bar, the easier the typo is to spot; one-edit slips are the ones that sneak past readers.

noline2olnine2onilne2onlien2onlinne1onlline1onlnie2onnline1
Edit distance from "online"

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "online"?
"online" is spelled O-N-L-I-N-E. The IPA pronunciation is /ˈɒnlaɪn/.
What does "online" mean?
As an adjective, "online" means: Of a system: connected (generally electrically) to a larger network.
What words are commonly confused with "online"?
"online" is commonly confused with "onsite", "onside", "outline". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "online"?
The IPA (International Phonetic Alphabet) transcription for "online" is /ˈɒnlaɪn/. Click the speaker icon on the pronunciation badge above to hear it spoken aloud where audio is available.
What is the origin of the word "online"?
1950, from on + line. 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 “online”

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

  • The one correct English spelling is O-N-L-I-N-E - every other letter order is a misspelling in standard orthography.
  • Say it as /ˈɒnlaɪn/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • Don't mix it up with “onsite” - see the side-by-side comparison. online vs onsite
  • 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 FrequencyWords open word-frequency list