Standard Lemma guide

unidirectional

adj · noun · 4 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

Each Play button uses your device's default local English voice, or a natural local fallback. The selected voice name appears after playback. This is synthesized speech, not a source recording.

  • Received-Pronunciation: /ˌjuː.nɪ.dɪˈɹɛk.ʃə.nəl
  • Received-Pronunciation: -daɪ-
  • Received-Pronunciation: -ˈɹɛkʃ.nəl/
  • Received-Pronunciation: [ˌjuː.nɨ.dɨˈɹɛk.ʃə.nl̩
  • Received-Pronunciation: -ˈɹɛkʃ.nl̩]
  • General-American: yo͞o'nĭ-dĭ-rĕkʹshə-nəl
  • General-American: -dī-
  • General-American: /ˌjuː.nɪ.dɪˈɹɛk.ʃə.nəl
  • General-American: -daɪ-/
  • General-American: [ˌjuː.nɪ̈.dɪ̈ˈɹɛk.ʃə.nl̩
  • General-American: -daɪ-]
  • Southern-England: Recorded audio is listed in the source snapshot.
  • rhymes with -ɛkʃənəl
  • rhymes with -ɛkʃnəl

1

adj

Meaning 1

Pertaining to only one direction, e.g.: where all component parts are aligned in the same direction in space.

Definition source: English Wiktionary via Wiktextract

Usage: not-comparable

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: simplex

Antonyms: none provided

2

adj

Meaning 2

Not subject to change or reversal of direction.

Definition source: English Wiktionary via Wiktextract

Usage: not-comparable

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

3

noun

Meaning 3

A fabric in which the majority of fibers run in the same single direction.

Definition source: English Wiktionary via Wiktextract

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

4

adjective

Meaning 4

operating or moving or allowing movement in one direction only

Definition source: Princeton WordNet 3.0

Examples

  • a unidirectional flow
  • a unidirectional antenna
  • a unidirectional approach to a problem

Meaning relationships

Synonyms: none provided

Antonyms: bidirectional

History

Etymology

Etymology tree Proto-Indo-European *ís? Proto-Indo-European *h1óynos Proto-Italic *oinos Old Latin oinos Latin ūnus Latin ūni-der. English uni- English direction English -al English directional English unidirectional From uni- + directional.

Across languages

Translations

16 source translations are retained for this English entry.

  • Bulgarian: еднопосочен (ednoposočen) — pertaining to only one direction
  • Catalan: unidireccional — pertaining to only one direction
  • Dutch: unidirectioneel — pertaining to only one direction
  • Dutch: eenrichtings- — pertaining to only one direction
  • Finnish: yksisuuntainen — pertaining to only one direction
  • Finnish: tasasuuntainen — pertaining to only one direction
  • French: unidirectionnel — pertaining to only one direction
  • Greek: ομοιοκατευθυνόμενος (omoiokatefthynómenos) — pertaining to only one direction
  • Hindi: एकदिश (ekdiś) — pertaining to only one direction
  • Hindi: एकदिशीय (ekdiśīya) — pertaining to only one direction
  • Hungarian: egyirányú — pertaining to only one direction
  • Irish: aontreoch — pertaining to only one direction
  • Polish: jednokierunkowy — pertaining to only one direction
  • Russian: однонапра́вленный (odnonaprávlennyj) — pertaining to only one direction
  • Swedish: enkelriktad — pertaining to only one direction
  • Ukrainian: односпрямо́ваний (odnosprjamóvanyj) — pertaining to only one direction