The Collaborative International Dictionary of English v.0.48:

Oft \Oft\ ([o^]ft; 115), adv. [AS. oft; akin to OS. & G. oft,
   OHG. ofto, Sw. ofta, Dan. ofte, Icel. opt, Goth. ufta; of
   uncertain origin. Cf. Often.]
   Often; frequently; not rarely; many times. [Poetic]
   --Chaucer.
   [1913 Webster]

         Oft she rejects, but never once offends. --Pope.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Oft \Oft\, a.
   Frequent; often; repeated. [Poetic]
   [1913 Webster]

WordNet (r) 3.0 (2006):

oft
    adv 1: many times at short intervals; "we often met over a cup
           of coffee" [syn: frequently, often, oftentimes,
           oft, ofttimes] [ant: infrequently, rarely,
           seldom]