The Collaborative International Dictionary of English v.0.48:

Impecunious \Im"pe*cu"ni*ous\, a. [L. im- not + pecunia money:
   cf. F. imp['e]cunieux.]
   Not having money; habitually without money; poor.
   [1913 Webster]

         An impecunious creature.                 --B. Jonson.
   [1913 Webster]

WordNet (r) 3.0 (2006):

impecunious
    adj 1: not having enough money to pay for necessities [syn:
           hard up, impecunious, in straitened
           circumstances(p), penniless, penurious, pinched]

Moby Thesaurus II by Grady Ward, 1.0:

30 Moby Thesaurus words for "impecunious":
   badly off, destitute, distressed, down to bedrock, embarrassed,
   feeling the pinch, hard up, ill off, in Queer Street,
   in narrow circumstances, in reduced circumstances,
   in straitened circumstances, land-poor, narrow, on the edge,
   out of pocket, pinched, poor, poorly off, poverty-stricken,
   reduced, short, short of cash, short of funds, short of money,
   squeezed, straitened, strapped, unmoneyed, unprosperous