a term that has been developed to restore the brand new concept of the term "gay" (stupid, dumb, etc. never HOMOSEXUAL). implying ones birthday celebration Nickname the title "Matthew" Abbreviation of an element resembling a CV Joint common to pre '86 Toyota sound Front Axles. Proper form: Birfield. A notorious poor link, often enhanced to Smurfields, Profields, etc, or changed totally with a Birfield Eliminator system.