The word derives from the Latin nidus or nest, via the French niche.
From the en.wikipedia.org
Nidus will offer life-sciences startups small labs and offices.
From the stltoday.com
Nidus, a business incubator, focuses on creating science-based companies with big growth potential.
From the stltoday.com
The effect is achieved due to small-size silver particles providing a high rate of delivery to the nidus of infection without causing allergic reactions.
From the businessweekly.co.uk
Her treatment was painful and ultimately unsuccessful, but the cells the doctors kept from her cancer became the nidus for a revolution in cell biology and research.
From the forbes.com
More examples
Focus: a central point or locus of an infection in an organism; "the focus of infection"
A nest in which spiders or insects deposit their eggs
(nidu) A type of cloud, probably cumulus (fluffy white clouds with flat bases).
Specific locality of a given disease; result of a unique combination of ecological factors that favors the maintenance and transmission of the disease organism.
A focus of infection; a cluster or nestlike structure.