‘Niche market ventures may become profitable even though they are by nature small in comparison to the mainstream marketplace, due to the benefits of specialization and focus on small identifiable market segments; even without the benefit of economy of scale. Niche markets may be ignored or discounted by large businesses due to what they consider to be small potential; this in turn is part of the process that makes the niche market available to smaller businesses. The key to capitalizing on a niche market is to find or develop a market niche that has customers who are accessible, that is growing fast enough, and that is not owned by one established vendor already.’
But, since you’re the guy with the PhD (three degrees = PhD, right?) in business, I’ll defer to your definition.