The Collaborative International Dictionary of English v.0.48:

Lief \Lief\, n.
   A dear one; a sweetheart. [Obs.] --Chaucer.
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The Collaborative International Dictionary of English v.0.48:

Lief \Lief\, adv.
   Gladly; willingly; freely; -- now used only in the phrases,
   had as lief, and would as lief; as, I had, or would, as lief
   go as not.
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         All women liefest would
         Be sovereign of man's love.              --Gower.
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         I had as lief the town crier spoke my lines. --Shak.
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         Far liefer by his dear hand had I die.   --Tennyson.
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   Note: The comparative liefer with had or would, and followed
         by the infinitive, either with or without the sign to,
         signifies prefer, choose as preferable, would or had
         rather. In the 16th century rather was substituted for
         liefer in such constructions in literary English, and
         has continued to be generally so used. See Had as
         lief, Had rather, etc., under Had.
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The Collaborative International Dictionary of English v.0.48:

Lief \Lief\ (l[=e]f), n.
   Same as Lif.
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The Collaborative International Dictionary of English v.0.48:

Lief \Lief\ (l[=e]f), a. [Written also lieve.] [OE. leef, lef,
   leof, AS. le['i]f; akin to OS. liof, OFries. liaf, D. lief,
   G. lieb, OHG. liob, Icel. lj?fr, Sw. ljuf, Goth. liubs, and
   E. love. [root]124. See Love, and cf. Believe, Leave,
   n., Furlough, Libidinous.]
   1. Dear; beloved. [Obs., except in poetry.] "My liefe
      mother." --Chaucer. "My liefest liege." --Shak.
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            As thou art lief and dear.            --Tennyson.
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   2.

   Note: (Used with a form of the verb to be, and the dative of
         the personal pronoun.) Pleasing; agreeable; acceptable;
         preferable. [Obs.] See Lief, adv., and Had as lief,
         under Had.
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               Full lief me were this counsel for to hide.
                                                  --Chaucer.
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               Death me liefer were than such despite.
                                                  --Spenser.
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   3. Willing; disposed. [Obs.]
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            I am not lief to gab.                 --Chaucer.
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            He up arose, however lief or loth.    --Spenser.
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WordNet (r) 3.0 (2006):

lief
    adv 1: in a willing manner; "this was gladly agreed to"; "I
           would fain do it" [syn: gladly, lief, fain]