Typically we say a word is camel cased if it starts with a capital letter, then has one or more lower case letters, and at least one other capital letter.

    /[A-Z][a-z]+[A-Z][A-Za-z]*/
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would match that. But you may have another definition of camel case. You may require no two capital letters may follow each other. Or that it may start with a lower case letter. Or in a very lose definition, anything consisting of letters is camel cased.

Please define what you exactly mean by CamelCase. (As an added benefit, if you can define how CamelCase looks like, you've almost written the regexp. Most regexp questions here aren't asked because people lack regexp knowledge - it's that they lack the ability (or will) to define what they want to match).