The Collaborative International Dictionary of English v.0.48:

Meddlesome \Med"dle*some\, a.
   Given to meddling; apt to interpose in the affairs of others;
   officiously intrusive. -- Med"dle*some*ness, n.
   [1913 Webster]

WordNet (r) 3.0 (2006):

meddlesome
    adj 1: intrusive in a meddling or offensive manner; "an
           interfering old woman"; "bustling about self-importantly
           making an officious nuisance of himself"; "busy about
           other people's business" [syn: interfering,
           meddlesome, meddling, officious, busy,
           busybodied]