The Collaborative International Dictionary of English v.0.48:

Yearn \Yearn\ (y[~e]rn), v. t. [imp. & p. p. Yearned; p. pr. &
   vb. n. Yearning.] [Also earn, ern; probably a corruption of
   OE. ermen to grieve, AS. ierman, yrman, or geierman, geyrman,
   fr. earm wretched, poor; akin to D. & G. arm, Icel. armr,
   Goth. arms. The y- in English is perhaps due to the AS. ge
   (see Y-).]
   To pain; to grieve; to vex. [Obs.] "She laments, sir, for it,
   that it would yearn your heart to see it." --Shak.
   [1913 Webster]

         It yearns me not if men my garments wear. --Shak.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

yearning \yearn"ing\, n.
   1. prolonged unfulfilled desire or need.

   Syn: longing.
        [WordNet 1.5]

The Collaborative International Dictionary of English v.0.48:

yearning \yearn"ing\, adj.
   1. full of longing or unfulfilled desire.

   Syn: wistful.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

yearning
    n 1: prolonged unfulfilled desire or need [syn: longing,
         yearning, hungriness]