http://en.wikipedia.org/wiki/Niche_market
Main Entry: 1niche
Pronunciation: \ˈnich also ˈnēsh or ˈnish\
Function: noun
Etymology: French, from Middle French, from nicher to nest, from Vulgar Latin *nidicare, from Latin nidus nest — more at nest
Date: 1611
1 a : a recess in a wall especially for a statue b : something that resembles a niche
2 a : a place, employment, status, or activity for which a person or thing is best fitted <finally found her niche> b : a habitat supplying the factors necessary for the existence of an organism or species c : the ecological role of an organism in a community especially in regard to food consumption d :
a specialized market
I don't know what else to tell you. The term niche has been used in business to indicate targeted specialized markets for, well, forever.