From WordNet (r) 2.0 (August 2003) [wn]:
frankfurter
n : a smooth-textured sausage of minced beef or pork usually
smoked; often served on a bread roll [syn: frank,
hotdog, hot dog, dog, wiener, wienerwurst,
weenie]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
frankfurter \frank"fur*ter\
A small cooked sausage of beef or beef and pork, usually 5 to
6 inches, sometimes as long as 12 inches in length; called
also frankforter, frankfort, frankfurt. It is commonly
eaten on a roll, called a hot dog bun.
Syn: wiener, hot dog[1].
[PJC]