niche (market, industry, hobby, etc.)
Commonly used in business and hobby contexts to refer to a specialized segment or area.
This company succeeded in a niche market.
Technical term in architecture for a recess in a wall, often for a statue or ornament.
ecological niche
Used in ecology to describe the role and position a species has in its environment.
See also: 生態的地位
His hobby is very niche, and few people understand it.
There is a niche in the church wall for a statue of a saint.
Overlap of ecological niches causes competition.