con1
  
  v.
 (cons, conning, conned)
 deceive (someone) into doing or believing something by lying to them.
n.
 a deception of this kind.
Etymology
  C19 (orig. US): abbrev. of confidence, as in confidence trick.
 
  
    
con2
  
  n.
 
(
usu. in phr. pros and cons)
 a disadvantage of or argument against something.
Etymology
  C16: from L. contra ‘against’.
 
  
    
con4
  
  v.
 (cons, conning, conned)
 direct the steering of (a ship).
n.
 
(
the con)
 the action or post of conning a ship.
Etymology
  C17: appar. a weakened form of obs. cond ‘conduct, guide’, from OFr. conduire.
 
  
    
con5
  
  v.
 (cons, conning, conned)
 archaic study attentively or learn by heart (a piece of writing).
Etymology
  ME cunne, conne, con, vars of can1.