The Collaborative International Dictionary of English v.0.48:

Plead \Plead\, v. t. [imp. & p. p. Pleaded (colloq. Pleador
   Pled); p. pr. & vb. n. Pleading.] [OE. pleden, plaiden,
   OF. plaidier, F. plaider, fr. LL. placitare, fr. placitum.
   See Plea.]
   1. To argue in support of a claim, or in defense against the
      claim of another; to urge reasons for or against a thing;
      to attempt to persuade one by argument or supplication; to
      speak by way of persuasion; as, to plead for the life of a
      criminal; to plead with a judge or with a father.
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            O that one might plead for a man with God, as a man
            pleadeth for his neighbor!            --Job xvi. 21.
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   2. (Law) To present an answer, by allegation of fact, to the
      declaration of a plaintiff; to deny the plaintiff's
      declaration and demand, or to allege facts which show that
      ought not to recover in the suit; in a less strict sense,
      to make an allegation of fact in a cause; to carry on the
      allegations of the respective parties in a cause; to carry
      on a suit or plea. --Blackstone. Burrill. Stephen.
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   3. To contend; to struggle. [Obs.] --Chaucer.
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