The Collaborative International Dictionary of English v.0.48:

Reedy \Reed"y\ (r[=e]d"[y^]), a.
   1. Abounding with reeds; covered with reeds. "A reedy pool."
      --Thomson .
      [1913 Webster]

   2. Having the quality of a reed in tone, that is, harsh and
      thin, as some voices.
      [1913 Webster]

WordNet (r) 3.0 (2006):

reedy
    adj 1: having a tone of a reed instrument [syn: reedy,
           wheezy]
    2: resembling a reed in being upright and slender [syn: reedy,
       reedlike]