The Collaborative International Dictionary of English v.0.48:

Nestle \Nes"tle\, v. i. [imp. & p. p. Nestled; p. pr. & vb. n.
   Nestling.] [AS. nestlian.]
   1. To make and occupy a nest; to nest. [Obs.]
      [1913 Webster]

            The kingfisher . . . nestles in hollow banks.
                                                  --L'Estrange.
      [1913 Webster]

   2. To lie close and snug, as a bird in her nest; to cuddle
      up; to settle, as in a nest; to harbor; to take shelter.
      [1913 Webster]

            Their purpose was to fortify in some strong place of
            the wild country, and there nestle till succors
            came.                                 --Bacon.
      [1913 Webster]

            The children were nestled all snug in their beds
            While visions of sugarplums danced in their heads.
                                                  --Clement
                                                  Clarke Moore
                                                  (A Visit From
                                                  St. Nicholas,
                                                  (a poem
                                                  [1823]) also
                                                  called The
                                                  Night Before
                                                  Christmas).
      [PJC]

   3. To move about in one's place, like a bird when shaping the
      interior of her nest or a young bird getting close to the
      parent; as, a child nestles.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Nestling \Nes"tling\, a.
   Newly hatched; being yet in the nest.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Nestling \Nes"tling\ n.
   1. A young bird which has not abandoned the nest. --Piers
      Plowman.
      [1913 Webster]

   2. A nest; a receptacle. [Obs.] --Bacon.
      [1913 Webster]

WordNet (r) 3.0 (2006):

nestling
    n 1: young bird not yet fledged [syn: nestling, baby bird]
    2: a young person of either sex; "she writes books for
       children"; "they're just kids"; "`tiddler' is a British term
       for youngster" [syn: child, kid, youngster, minor,
       shaver, nipper, small fry, tiddler, tike, tyke,
       fry, nestling]