Portmanteau morph

Portmanteau is a traditional term used for a type of fusion of two morphemes into one. A portmanteau morph is a phonological sequence that cannot be analyzed into smaller units in terms of form but has two or more distinct components in terms of meaning.

Example
In Latin inflection, the suffix -r (e.g. fer-a-r 'I will be carried') can be analyzed as containing three morphemes (first person, singular, passive), realized as a single portmanteau morph.

One could regard the English word took to be a portmanteau representation of the verb take and the past tense suffix -ed.

Origin
The term was proposed by Hockett (1947:333).

Links
Utrecht Lexicon of Linguistics