In the late 1950's puppet master Jim Henson created some puppet characters and called them the Muppets.
Since the 1950's the Muppets have been entertaining children and adults alike with their silly antics.
However in Brittan, Ireland, Australia, and New Zealand, the word muppet has become a mild term of abuse.
When using muppet as a mild term of abuse the first thing to notice is the difference in spelling, the puppets created by Jim Henson and now owed by the Disney Corporation are spelt with a capital "M", as in The Muppets, and when we call someone a muppet we spell it with a lowercase "m".
When you call someone a muppet (lower case) you are suggesting that they stupid or silly.
For example: "John its six o'clock, you were supposed to be here an hour ago, you muppet!"
Calling someone a muppet should not cause them offensive, and has even been used in street advertising, however as a learner of English, remember if you are going to call someone a muppet, be sure that they have a good sense of humour.
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