Such a definition of "portmanteau word" overlaps with the grammatical term contraction, and linguists avoid using the former term in such cases. As an example: the words do + not become the contraction don't, a single word that represents the meaning of the combined words.
An arguably humorous synonym for "portmanteau word" is "frankenword", itself a portmanteau word, blending "Frankenstein" and "word".
Carroll uses the word again when discussing lexical selection:
Humpty Dumpty's theory, of two meanings packed into one word like a portmanteau, seems to me the right explanation for all. For instance, take the two words "fuming" and "furious." Make up your mind that you will say both words ... you will say "frumious.".Carroll suggests here a double metaphor. The original meaning of the word 'portmanteau' is a form of suitcase containing two separated hinged compartments; thus: two distinct words, packed as one. The word 'portmanteau' is itself a 'portmanteau word', deriving from the two French words porter (to carry) and manteau (cloak or mantle).
Many neologisms are examples of blends, but many blends have become part of the lexicon. In Punch in 1896, the word brunch (breakfast + lunch) was introduced as a "portmanteau word". In 1964, the newly independent African republic of Tanganyika and Zanzibar chose the portmanteau word Tanzania as its name.
Portmanteau words may be produced by joining together proper nouns with common nouns, such as "gerrymandering," which refers to the scheme of Massachusetts Governor Elbridge Gerry for politically contrived redistricting: one of the districts created had the semblance of a salamander in outline. Two proper names can also be used in creating a portmanteau word in reference to the partnership between people, especially in a case where both persons are well known, or sometimes to produce epithets such as "Billary" (referring to former United States president Bill Clinton and Hillary Rodham Clinton). In this example of recent American political history, the purpose for blending is not so much to combine the meanings of the source words but "to suggest a resemblance of one named person to the other" and the effect is often derogatory, as linguist Benjamin Zimmer notes.
Portmanteaux (or portmanteaus) can also be created by attaching a prefix or suffix from one word to give that association to other words. Subsequent to the Watergate Scandal, it became popular to attach the suffix "-gate" to other words to describe contemporary scandals, e.g. "Filegate" for the White House FBI files controversy. Likewise, the suffix "-holism" or "-holic", taken from the word "alcoholism" or "alcoholic", can be added to a noun, creating a word that describes an addiction to that noun. Chocoholic, for example, means a person who is addicted to chocolate.
Portmanteau words can be used to describe bilingual speakers who use words from both languages while speaking. For instance a person would be considered speaking "Spanglish" if they are using both Spanish and English words to voice a complete thought.