From The Collaborative International Dictionary of English v.0.48 [gcide]:
Niche \Niche\ (n[i^]ch), noun [F., fr. It. nicchia, prop., a shell-like recess in a wall, fr. nicchio a shellfish, mussel, fr. L. mytilus.] A cavity, hollow, or recess, generally within the thickness of a wall, for a statue, bust, or other erect ornament. Hence, any similar position, literal or figurative.
From WordNet (r) 3.0 (2006) [wn]:
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