The Collaborative International Dictionary of English v.0.48:

Respectable \Re*spect"a*ble\ (-?-b'l), a. [F. respectable, LL.
   respectabilis.]
   1. Worthy of respect; fitted to awaken esteem; deserving
      regard; hence, of good repute; not mean; as, a respectable
      citizen. "The respectable quarter of Sicca." --J. H.
      Newman.
      [1913 Webster]

            No government, any more than an individual, will
            long be respected, without being truly respectable.
                                                  --Madison.
      [1913 Webster]

   2. Moderate in degree of excellence or in number; as, a
      respectable performance; a respectable audience.
      [1913 Webster] --Re*spect"a*ble*ness,n. --
      Re*spect"a*bly, adv.
      [1913 Webster]

WordNet (r) 3.0 (2006):

respectably
    adv 1: to a tolerably worthy extent; "he did respectably well
           for his age" [syn: respectably, creditably]
    2: in a decent and morally reputable manner; "the film ends with
       the middle-aged romancers respectably married"