[1] : The Collaborative International Dictionary of English v.0.48

portmanteau word \portman"teau word`\, n. see portmanteau.
   a word formed by joining two others; -- as, smog is formed
   from smoke and fog.
   wordnet 1.6
see also:
portmanteau smoke fog 

[2] : WordNet (r) 2.0

portmanteau word
     n : a new word formed by joining two others and combining their
         meanings; "`smog' is a blend of `smoke' and `fog'";
         "`motel' is a portmanteau word made by combining `motor'
         and `hotel'"; "`brunch' is a well-known portmanteau"
         syn: blend, portmanteau
see also:
blend portmanteau 

[3] : Moby Thesaurus II by Grady Ward, 1.0

22 moby thesaurus words for "portmanteau word":
   ambiguity, amphibology, blend, contamination, counterword,
   double entendre, equivocal, equivocality, equivocation, equivoque,
   hybrid, hybrid word, hybridism, macaronic, macaronicism,
   polysemant, portmanteau, portmantologism, pun,
   squinting construction, telescope word, weasel word

Portmanteau >> P Words
Portmanteau, definition of term: Portmanteau
portmanteau_pag1.html

Portmanteau Wor >> P Words
Portmanteau Wor, definition of term: Portmanteau Wor
portmanteau+wor_pag1.html

Root Word >> R Words
Root Word, definition of term: Root Word
root+word_pag1.html

Nonce Word >> N Words
Nonce Word, definition of term: Nonce Word
nonce+word_pag1.html

Microsoft Word >> M Words
Microsoft Word, definition of term: Microsoft Word
microsoft+word_pag1.html

Compound Word >> C Words
Compound Word, definition of term: Compound Word
compound+word_pag1.html

Entry Word >> E Words
Entry Word, definition of term: Entry Word
entry+word_pag1.html

Key Word >> K Words
Key Word, definition of term: Key Word
key+word_pag1.html

Cognate Word >> C Words
Cognate Word, definition of term: Cognate Word
cognate+word_pag1.html