I'm partially trained in anthropology and would love to provide some insight. While terms like 'ritual' and 'ceremonial' certainly indicate religious undertones, they are delineated in an anthropological context.

For example, an anthro operational definition for 'ritual' would be "actions with intentional symbolic meaning undertaken for a specific cultural purpose", where the cultural purpose could be childhood development (rites of adulthood), religious as previously mentioned, or perhaps just a fun activity within the society.

I say all of this but understand that this article isn't necessarily geared towards only anthropologists, and operational definitions may be in order. Just my 2cents