1. [v]  mix up or confuse; "He muddled the issues"
2. [v]  become rotten; of eggs

ADDLE is a 5 letter word that starts with A.

1. \Ad"dle\, n. [OE. adel, AS. adela, mud.]
   1. Liquid filth; mire. [Obs.]
   2. Lees; dregs. [Prov. Eng.] --Wright.
   

2. \Ad"dle\, a.
   Having lost the power of development, and become rotten, as
   eggs; putrid. Hence: Unfruitful or confused, as brains;
   muddled. --Dryden.
   

3. \Ad"dle\, v. t. & i. [imp. & p. p. {Addled}; p. pr. & vb.
   n. {Addling}.]
   To make addle; to grow addle; to muddle; as, he addled his
   brain. ``Their eggs were addled.'' --Cowper.
   

4. \Ad"dle\, v. t. & i. [OE. adlen, adilen, to gain, acquire;
   prob. fr. Icel. ["o][eth]lask to acquire property, akin to
   o[eth]al property. Cf. {Allodial}.]
   1. To earn by labor. [Prov. Eng.] --Forby.
   2. To thrive or grow; to ripen. [Prov. Eng.]
            Kill ivy, else tree will addle no more. --Tusser.