Roselle (rōzĕlˈ) [key], borough (1990 pop. 20,314), Union co., NE N.J.; set off from Linden 1890 and inc. 1894. Chiefly residential, the borough has some industry. Thomas Edison had a laboratory there, and Roselle was the world's first community to have incandescent bulbs light its streets. Abraham Clark, a signer of the Declaration of Independence, was born in Roselle.