Duden

What the picture shows

A bright yellow book with the word "DUDEN" printed in large black letters along its spine and a white number "1" on the front cover, shown standing upright against a plain white background. Chatters likely use this emote to signal that a message is grammatically correct, to correct someone's spelling, or to jokingly act like a dictionary authority.

No measured meaning yet. Used 1 times in 1 channels this month; one is written once chat gives enough evidence.