Standard Lemma guide

m/o

noun · 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

noun

Meaning 1

Abbreviation of month(s) old.

Definition source: English Wiktionary via Wiktextract

Usage: abbreviation, alt-of

Examples

  • baby Jackie is 5 m/o

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

noun

Meaning 2

molar percent (percentage calculated by relative molarity [number of atoms or molecules])

Definition source: English Wiktionary via Wiktextract

Topics: chemistry, natural-sciences, physical-sciences

Examples

  • explosive limits for mixtures of [...] 91.9 m/o chlorine and 8.1 m/o hydrogen

Meaning relationships

Synonyms: a/o, mol%

Antonyms: none provided

History

Etymology

No etymology was provided for this word.