Merriam-Webster’s Vocabulary ...

The name Webster alone is no guarantee of excellence. It is used by a number
of publishers and may serve mainly to mislead an unwary buyer.
Merriam-Webster™ is the name you should look for when you consider the
purchase of dictionaries or other fine reference books. It carries the reputation
of a company that has been publishing since 1831 and is your assurance of
quality and authority.