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Historically, the word usually has been used as a noun describing a type of man, or as an interjection. The tone and inflection of the word “dude” are used to convey the various meanings. For example, someone may be a “surfer dude.” “Dude” is considered to be slang, similar to the word “man”. “Dude” is also used alone in a sentence as an interjection denoting a feeling of surprise, happiness, disappointment, amazement or other emotions. As an interjection, a short, clipped “dude!” might be used to convey annoyance with someone, while a long, drawn-out “duuuude” conveys amazement. The word might also be used almost anywhere in a sentence in order to convey such sentiments in conversation, as in, “Listen, dude, we have to go.”