The Collaborative International Dictionary of English v.0.48:
Nickar nut \Nick"ar nut`\, Nickar tree \Nick"ar tree`\ (Bot.) Same as Nicker nut, Nicker tree. [1913 Webster]The Collaborative International Dictionary of English v.0.48:
Nicker tree \Nick"er tree`\ (Bot.) The plant producing nicker nuts. [Written also neckar tree and nickar tree.] [1913 Webster]