Wordnet 3.0
NOUN (1)
1. 
 a person with a strong desire for something; 
- Example: "a longer for money"- Example: "a thirster after blood"- Example: "a yearner for knowledge"[syn: longer, thirster, yearner]
The Collaborative International Dictionary of English v.0.48:
Thirster \Thirst"er\, n.
   One who thirsts.
   [1913 Webster]
WordNet (r) 3.0 (2006):
thirster
    n 1: a person with a strong desire for something; "a longer for
         money"; "a thirster after blood"; "a yearner for knowledge"
         [syn: longer, thirster, yearner]