A word which combines the meaning of two words (or, rarely, more than two words), formed by combining the words, usually, but not always, by adjoining the first part of one word and the last part of the other, the adjoining parts often having a common vowel; for example, smog, formed from smoke and fog
A word formed by merging the sounds and meanings of two different words, as chortle, from chuckle and snort. a portmanteau word is made by combining the sound and meaning of two other words, for example 'edutainment' combines 'education' and 'entertainment'