The Collaborative International Dictionary of English v.0.48:

Pinguicula \Pin*guic"u*la\, n. [NL., fr. L. pinguiculus somewhat
   fat, fattish.] (Bot.)
   See Butterwort.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Butterwort \But"ter*wort`\, n. (Bot.)
   A genus of low herbs (Pinguicula) having simple leaves
   which secrete from their glandular upper surface a viscid
   fluid, to which insects adhere, after which the margin
   infolds and the insects are digested by the plant. The
   species are found mostly in the North Temperate zone.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Pinguicula
    n 1: butterworts: a large genus of almost stemless carnivorous
         bog plants; Europe and America to Antarctica [syn:
         Pinguicula, genus Pinguicula]