phi
noun
Simple meaning
A visual illusion whereby a sequential pattern of lights produces a false sense of motion.
Pronunciation
Say it like this:
fyIPA pronunciation (US)
ˈfaɪ
This word is pronounced essentially the same in American and British English, so one transcription covers both.
IPA (International Phonetic Alphabet) is a standard way of writing speech sounds.
Definition
Everyday modern meanings first, grouped by part of speech.
noun
A visual illusion whereby a sequential pattern of lights produces a false sense of motion.
mathematics
The golden ratio.
Φ, the 21st letter of the Euclidean and modern Greek alphabet, usually romanized as "ph".
Word at a Glance
- Difficulty
- B1 · Intermediate (estimated)
- Frequency
- Common
- Typical Use
- Everyday English
Word Aura™
How this word commonly comes across.
Aura for this meaning
This meaning: A visual illusion whereby a sequential pattern of lights produces a false sense of motion.
Used this way, phi is a reasonably familiar word that usually carries little praise or criticism of its own. It usually sounds natural in a wide range of settings.
- Emotional tone
- Neutral
- Formality
- Neutral
- Intensity
- Not strongly marked
- How common
- Moderately common
- Connotation
- Matter-of-fact
- Usage feel
- Neutral and straightforward
Word Aura describes common impressions, not a measurement. Tone changes with sentence, speaker, relationship and situation.
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Common Patterns and Combinations
How this word naturally appears with others.
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Other combinations
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Words can change meaning depending on context.
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Dictionary data from Wiktionary via the Free Dictionary API. Simple meanings, combinations and word intelligence are built from verified reference data, no AI is used to load this page.