Scottish crest badge is a heraldic badge worn to show allegiance to an individual or membership in a specific Scottish clan. Crest badges are commonly called “clan crests“, but this is a misnomer; there is no such thing as a collective clan crest, just as there is no such thing as a clan coat of arms..
Crest badges consist of a heraldic crest and a motto/slogan. These elements are heraldic property and protected by law in Scotland. Crest badges may be worn by anyone, but those who are not legally entitled to the heraldic elements wear a crest badge that incorporates a strap and buckle, which indicates that the wearer is a follower of the individual who owns the crest and motto.
Crest badges are commonly worn by members of Scottish clans. These badges usually consist of elements from the clan chief’s coat of arms. Clan members who wear their chief’s crest and motto surrounded by a strap and buckle show they are members of the chief’s clan (family). Although so-called “clan crests” are commonly bought and sold, the heraldic crest and motto belong to the chief alone and never to the individual clan member.
Crest badges, much like clan tartan, do not have a long history and owe much to Victorian era ramanticism, having only been worn on the bonnet since the 19th century. The original badges used by clans are said to have been specific plants worn in bonnets or hung from a pole or spear.

Crowberry, attributed to the Camerons, Macfies, and Macleans.
Oak, attributed to the Buchanans,Camerons, Kennedys, Macfies, Stewarts, and Woods.
Clan Cameron Crest Badge

Arms of The Lochiel Sir Donald Cameron of Lochiel, the 26th Chief of Clan Cameron (1910 – 2004)