DuckCorp Dico

Found 2 definitions

1.                 From Japanese-English FreeDict Dictionary ver. 0.1:
                   
   
   
                   
                     
   Φ /(el)fˈi(ja)/, φ /(el)fˈi(ja)/, ϕ /(el)lˈetəsˈandˈiːɡˈo(ja)/, ファイ /ɸˈäi/, フィー /ɸˈiː/
   1. (noun (common) (futsuumeishi))
   phi
   2. (prefix)
    (suffix)
    (confusion with ⌀ (ø), properly prefix read まる, also pronounced パイ)
   diameter (units assumed, esp. mm)
   
                   
                 

2.                 From Japanese-English FreeDict Dictionary ver. 0.1:
                   
   
   
                   
                     
   Φ /(el)fˈi(ja)/, φ /(el)fˈi(ja)/, ϕ /(el)lˈetəsˈandˈiːɡˈo(ja)/, ファイ /ɸˈäi/, フィー /ɸˈiː/
   1. (noun (common) (futsuumeishi))
   phi
   2. (prefix)
    (suffix)
    (confusion with ⌀ (ø), properly prefix read まる, also pronounced パイ)
   diameter (units assumed, esp. mm)