lenticular galaxylenticular galaxy NGC 5866 in the northern constellation Dracolenticular galaxyn. A galaxy having a central bulge surrounded by a flattened disk that contains numerous stars but relatively little interstellar matter, creating a conspicuous pattern of spiral arms.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.