Standard Lemma guide

oct-

prefix · 2 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

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No pronunciation record was provided for this word.

1

prefix

Meaning 1

Form of octa- or octo- used before a vowel.

Definition source: English Wiktionary via Wiktextract

Usage: form-of, morpheme

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

prefix

Meaning 2

Used for the digit eight to form systematic element names of elements whose existence has been predicted, and which have not yet been given a trivial name.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Topics: chemistry, natural-sciences, physical-sciences

Examples

  • un- (“1”) + bi- (“2”) + oct- (“8”) + -ium (element suffix) → unbioctium (“element 128”)

Meaning relationships

Synonyms: none provided

Antonyms: none provided

History

Etymology

No etymology was provided for this word.