Source : Webster's Revised Unabridged Dictionary (1913)

Belonging \Be*long"ing\, n. [Commonly in the pl.]
   1. That which belongs to one; that which pertains to one;
      hence, goods or effects. ``Thyself and thy belongings.''
      --Shak.

   2. That which is connected with a principal or greater thing;
      an appendage; an appurtenance.

   3. Family; relations; household. [Colloq.]

            Few persons of her ladyship's belongings stopped,
            before they did her bidding, to ask her reasons.
                                                  --Thackeray.

Belong \Be*long"\, v. i. [imp. & p. p. {Belonged}; p. pr. & vb.
   n. {Belonging}.] [OE. belongen (akin to D. belangen to
   concern, G. belangen to attain to, to concern); pref. be- +
   longen to desire. See {Long}, v. i.]

   Note: [Usually construed with to.]
   1. To be the property of; as, Jamaica belongs to Great
      Britain.

   2. To be a part of, or connected with; to be appendant or
      related; to owe allegiance or service.

            A desert place belonging to . . . Bethsaids. --Luke
                                                  ix. 10.

            The mighty men which belonged to David. --1 Kings i.
                                                  8.

   3. To be the concern or proper business or function of; to
      appertain to. ``Do not interpretations belong to God ?''
      --Gen. xl. 8.

   4. To be suitable for; to be due to.

            Strong meat belongeth to them that are of full age.
                                                  --Heb. v. 14.

            No blame belongs to thee.             --Shak.

   5. To be native to, or an inhabitant of; esp. to have a legal
      residence, settlement, or inhabitancy, whether by birth or
      operation of law, so as to be entitled to maintenance by
      the parish or town.

            Bastards also are settled in the parishes to which
            the mothers belong.                   --Blackstone.

Source : WordNet®

belonging
     n : happiness felt in a secure relationship; "with his
         classmates he felt a sense of belonging"