From Wiktionary, the free dictionary
See also: Φ [U+03A6 GREEK CAPITAL LETTER PHI] ,
ϕ [U+03D5 GREEK PHI SYMBOL] ,
ф [U+0444 CYRILLIC SMALL LETTER EF] ,
Ф [U+0424 CYRILLIC CAPITAL LETTER EF] ,
Փ [U+0553 ARMENIAN CAPITAL LETTER PIWR] , and φ. ϕ ( mathematics, technical ) Named by mathematician Mark Barr after Ancient Greek Φειδίας ( Pheidías ) (Phidias ), who supposedly used the golden ratio in his work.
φ
( mathematics ) golden ratio , an irrational number with a value of approximately 1.618033988 which expresses the relationship that the sum of two quantities is to the larger quantity as the larger is to the smaller.φ
( mathematics ) Euler's totient function , an arithmetic function that counts totatives ( UPA ) voiceless labiodental fricative (IPA [ɸ] ).( Cyrillic, phonetics ) [ɸ] ).Derived from its majuscule counterpart Φ .
φ • (ph ) (lowercase , uppercase Φ
Lower-case phi (φεῖ Greek alphabet . It represented the voiceless aspirated bilabial plosive /pʰ/ and later the voiceless labiodental fricative /f/ . It is preceded by υ and followed by χ . See also phi
( Greek-script letters) Α α Β β Γ γ Δ δ Ε ε Ζ ζ Η η Θ θ Ι ι Κ κ Λ λ Μ μ Ν ν Ξ ξ Ο ο Π π Ρ ρ Σ σ ς Τ τ Υ υ Φ φ Χ χ Ψ ψ Ω ω ( non-Classical letters ) Ϝ ( W ) ϝ ( w ) , Ͷ ͷ Ͱ ( H ) ͱ ( h ) , Ϻ ( S ) ϻ ( s ) , Ϟ ϟ Ϙ ( Q ) ϙ ( q ) , Ͳ ( S ) ͳ ( s ) ( punctuation ) · ⸳ . ; ( diacritics ) ᾿ ῾ ◌́ ◌̀ ῀ ¨ φ • (f ) (lowercase , uppercase Φ
The lower case letter phi (φι ), the 21st letter of the modern Greek alphabet . ( Greek-script letters) Α α Β β Γ γ Δ δ Ε ε Ζ ζ Η η Θ θ Ι ι Κ κ Λ λ Μ μ Ν ν Ξ ξ Ο ο Π π Ρ ρ Σ σ ς Τ τ Υ υ Φ φ Χ χ Ψ ψ Ω ω ( non-Classical letters ) Ϝ ( W ) ϝ ( w ) , Ͷ ͷ Ͱ ( H ) ͱ ( h ) , Ϻ ( S ) ϻ ( s ) , Ϟ ϟ Ϙ ( Q ) ϙ ( q ) , Ͳ ( S ) ͳ ( s ) ( punctuation ) · ⸳ . ; ( diacritics ) ᾿ ῾ ◌́ ◌̀ ῀ ¨ φ΄ ͵φ 
