Insignia are badges, emblems, or symbols that show someone's rank, membership, or achievement. A police officer's badge is an insignia that identifies them as law enforcement. A scout's uniform covered in colorful patches displays insignia for each skill they've mastered. Military officers wear different insignia on their uniforms to show their rank: a general's stars look different from a lieutenant's bars.

You'll often see insignia on uniforms, flags, and official documents. A school might have its own insignia, perhaps a logo with a lion and the school's founding date. Sports teams wear insignia on their jerseys. Even video game characters often have insignia on their armor or clothing to show which faction or team they belong to.

Notice that while “insignia” looks plural, it can work as either singular or plural. You might say “the insignia is displayed on the door” or “the insignia are sewn onto the sleeve.” Both are correct in modern English. The important thing to remember is that insignia identify and communicate something important about the person or group wearing them.