What is Brand Language?

Legal Definition
Brand language is the body of words, phrases, and terms that an organization uses to describe its purpose or in reference to its products. Brand language is used in marketing to help consumers connect specific words or ideas to specific companies or products. When developing a brand language word choice and tone are the two fundamental components. Word choice is the vocabulary that is used in the marketing or advertising, while tone refers to the attitude of the advertisement. Tone is not limited to language, it can also be incorporated through visual elements as well as delivery.

Brand language is a part of verbal brand identity, includes naming of both corporation and the products they sell as well as taglines, voice, and tone. Another benefit of developing a brand language is the ability for a corporation or product to be recognizable across international borders, while other advertising codes can be misinterpreted, words can be translated to ensure brand unity.
-- Wikipedia