The Collaborative International Dictionary of English v.0.48:

Excrete \Ex*crete"\, v. t. [imp. & p. p. Excreted; p. pr. &
   vb. n. Excreting.] [L. excretus, p. p. of excernere to sift
   out, discharge; ex out + cernere to sift, separate. See
   Crisis.]
   To separate and throw off; to excrete urine. "The mucus thus
   excreted." --Hooper.
   [1913 Webster]

WordNet (r) 3.0 (2006):

excrete
    v 1: eliminate from the body; "Pass a kidney stone" [syn:
         excrete, egest, eliminate, pass]

Moby Thesaurus II by Grady Ward, 1.0:

31 Moby Thesaurus words for "excrete":
   bleed, discharge, effuse, egest, eliminate, emit, exfiltrate,
   extravasate, exudate, exude, filter, filtrate, give off, give out,
   lactate, leach, lixiviate, ooze, pass, percolate, produce, reek,
   secern, secrete, seep, strain, tear, transpire, transude, water,
   weep