Kastom is a pijin word used to refer to tradition

Tradition

A tradition is a ritual, belief or object passed down within a society, still maintained in the present, with origins in the past. Common examples include holidays or impractical but socially meaningful clothes , but the idea has also been applied to social norms such as greetings...

al culture, including religion, economics, art and magic in Melanesia

Melanesia

Melanesia is a subregion of Oceania extending from the western end of the Pacific Ocean to the Arafura Sea, and eastward to Fiji. The region comprises most of the islands immediately north and northeast of Australia...

.

The term is the generally accepted anthropology

Anthropology

Anthropology is the study of humanity. It has origins in the humanities, the natural sciences, and the social sciences. The term "anthropology" is from the Greek anthrōpos , "man", understood to mean mankind or humanity, and -logia , "discourse" or "study", and was first used in 1501 by German...

 term to describe such phenomenon as well as the common and lay term used in everyday language.

The word derives from the Australian English pronunciation of custom but crosses meanings that incorporate:

• Custom (law)
  Custom (law)
  Custom in law is the established pattern of behavior that can be objectively verified within a particular social setting. A claim can be carried out in defense of "what has always been done and accepted by law." Customary law exists where:...
  
   or customary law,
• Norm (sociology)
  Norm (sociology)
  Social norms are the accepted behaviors within a society or group. This sociological and social psychological term has been defined as "the rules that a group uses for appropriate and inappropriate values, beliefs, attitudes and behaviors. These rules may be explicit or implicit...
  
  ,
• Convention (norm)
  Convention (norm)
  A convention is a set of agreed, stipulated or generally accepted standards, norms, social norms or criteria, often taking the form of a custom....
  
   and
• Tradition
  Tradition
  A tradition is a ritual, belief or object passed down within a society, still maintained in the present, with origins in the past. Common examples include holidays or impractical but socially meaningful clothes , but the idea has also been applied to social norms such as greetings...
  
  

It is consistent in spelling across most of the many variations in pidjin and pisin across the region.

Kastom is mostly not written only passed down through teachings and stories. It is concentrated through:

• Kastom House - sites where objects and rituals are stored.
• Kastom stories - myths, legends and communal histories.
• ritual objects - objects of special power, significance and symbolism.

The use of the word is slightly different in the different countries and cultures of Melanesia.

There are designated Kastom villages in Vanuatu

Vanuatu

Vanuatu , officially the Republic of Vanuatu , is an island nation located in the South Pacific Ocean. The archipelago, which is of volcanic origin, is some east of northern Australia, northeast of New Caledonia, west of Fiji, and southeast of the Solomon Islands, near New Guinea.Vanuatu was...

which are open to tourists, dedicated to preserving Kastom.