[1] : WordNet (r) 2.0

eff
     v : have sexual intercourse with; "this student sleeps with
         everyone in her dorm"; "adam knew eve"; "were you ever
         intimate with this man?" syn: roll in the hay, love,
          make out, make love, sleep with, get laid, have
         sex, know, do it, be intimate, have intercourse,
          have it away, have it off, screw, fuck, jazz,
         hump, lie with, bed, have a go at it, bang, get
         it on, bonk
see also:
roll in the hay love make out make love sleep with get laid 
have sex know do it be intimate have intercourse 
have it away have it off screw fuck jazz 
hump lie with bed have a go at it bang 
get it on bonk 

[2] : Virtual Entity of Relevant Acronyms (Version 1.9, June 2002)

eff
     electronic frontier foundation internet, org.
     
     

[3] : The Free On-line Dictionary of Computing (27 SEP 03)

eff
     
        electronic frontier foundation
     
     
see also:
electronic frontier foundation 

Eff >> E Words
Eff, definition of term: Eff
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