niche

A niche is a specialized part of a market for products or services or a little separated area in a room. (noun)

An example of a niche is a market for beagle products, which is a niche in the market of dog products as a whole.
An example of a niche is a little windowseat in a house tucked into a corner.

See niche in Webster's New World College Dictionary

noun

a recess or hollow in a wall, as for a statue, bust, or vase
a place or position particularly suitable to the person or thing in it
any small, specialized business market
Ecol.
1. the particular role of an individual species or organism in its community and its environment, including its position in the food cycle and its behavior
2. the specific space occupied by an organism within its habitat

transitive verb niched, niching

to place in or as in a niche

See niche in American Heritage Dictionary 4

(nĭch, nēsh)

noun

A recess in a wall, as for holding a statue or urn.
A cranny, hollow, or crevice, as in rock.
a. A situation or activity specially suited to a person's interests, abilities, or nature: found her niche in life.
b. A special area of demand for a product or service: “One niche that is approaching mass-market proportions is held by regional magazines” (Brad Edmondson).
Ecology
a. The function or position of an organism or population within an ecological community.
b. The particular area within a habitat occupied by an organism.