Portmanteau (noun)

1. A large suitcase that opens into two hinged compartments.
2. A word formed by combining the sounds and meanings of two different words, as in smog (smoke and fog).

Origin:

Mid 19th century: from french, literally "carrier"s case", from porter "to carry" + manteau "cloak".

Examples:

1. He was carrying a large portmanteau on his trip.
2. The portmanteau was filled with clothes for the week long trip.
3. The word "brunch" is a portmanteau of "breakfast" and "lunch".
4. The word "motel" is a portmanteau of "motor" and "hotel".
5. The term "smog" is a portmanteau of "smoke" and "fog".