Standard Lemma guide

phi

name · noun · 6 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.

  • /faɪ/
  • US: Recorded audio is listed in the source snapshot.
  • rhymes with -aɪ
  • homophone: fie
  • /fiː/
  • US: Recorded audio is listed in the source snapshot.
  • rhymes with -iː
  • homophone: fee
  • CMU ARPABET: F AY1 Digits mark lexical stress: 1 primary, 2 secondary, 0 unstressed.

1

name

Meaning 1

Abbreviation of Philadelphia.

Definition source: English Wiktionary via Wiktextract

Usage: abbreviation, alt-of

Topics: hobbies, lifestyle, sports

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

noun

Meaning 2

Φ, the 21st letter of the Euclidean and modern Greek alphabet, usually romanized as "ph".

Definition source: English Wiktionary via Wiktextract

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

3

noun

Meaning 3

The golden ratio.

Definition source: English Wiktionary via Wiktextract

Topics: mathematics, sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

4

noun

Meaning 4

A visual illusion whereby a sequential pattern of lights produces a false sense of motion.

Definition source: English Wiktionary via Wiktextract

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

5

noun

Meaning 5

Initialism of protected health information.

Definition source: English Wiktionary via Wiktextract

Usage: abbreviation, alt-of, initialism, uncountable

Topics: law, medicine, sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

6

noun

Meaning 6

the 21st letter of the Greek alphabet

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

Broader terms: letter, letter of the alphabet, alphabetic character

History

Etymology

From Late Latin phi, from Ancient Greek φεῖ (pheî).

Across languages

Translations

32 source translations are retained for this English entry.

  • Arabic: فَاي (fay) — Greek letter
  • Asturian: fi — Greek letter
  • Catalan: fi — Greek letter
  • Chinese Mandarin: 弗愛 /弗爱 — Greek letter
  • Chinese Mandarin: 佛爱 (fú'ài) — Greek letter
  • Chinese Mandarin: 斐 (fěi) — Greek letter
  • Czech: fí — Greek letter
  • Dutch: phi — Greek letter
  • Esperanto: fio — Greek letter
  • Finnish: fii — Greek letter
  • French: phi — Greek letter
  • German: Phi — Greek letter
  • Greek: φι (fi) — Greek letter
  • Ancient Greek: φεῖ (pheî) — Greek letter
  • Hebrew: פִי (fi) — Greek letter
  • Hungarian: fi — Greek letter
  • Interlingua: phi — Greek letter
  • Irish: fí — Greek letter
  • Japanese: ファイ (fai) — Greek letter
  • Japanese: フィ (fi) — Greek letter
  • Japanese: ピー (pī) — Greek letter
  • Korean: 피 (pi) — Greek letter
  • Macedonian: фи (fi) — Greek letter
  • Malay: fi — Greek letter
  • Persian: فی (fi) — Greek letter
  • Polish: fi — Greek letter
  • Polish: phi — Greek letter
  • Portuguese: fi — Greek letter
  • Romanian: fi — Greek letter
  • Russian: фи (fi) — Greek letter
  • Slovak: fí — Greek letter
  • Spanish: fi — Greek letter